A Gentle Introduction to Robotics

Giving a Presentation

In any group endeavor, you will need to communicate with others. One type of communication is giving a presentation. Presentations are arrangements in which a person (the presenter) gives (presents) information (also confusingly called the presentation) to others. Presentations can have many forms, but typically involve one person standing in front of a lot of other people and doing a lot of talking, while showing visuals (commonly called “slides” after an old technology, or “foils” after an even older technology), and providing summary or detailed supporting documents (handouts). There are typically two deliverables of a presentation: information at the moment, and a durable reminder of that information for later use.

Sometimes, the motivation of a presentation is only to inform. For example, an archaeologist might produce a presentation on ancient Mesopotamian water technology. While interesting and possibly fascinating, this information likely has little application in the day to day world, and is unlikely to affect future action. But most presentations are oriented to the future: they are intended to influence a decision on a course of action. To do this, the information presented must be:

Relevant, authoritative, and actionable makes a presentation useful. It does not necessarily make it good. The activity of presentation itself can make a useful presentation good. (It cannot rescue a useless presentation.) A presentation poorly presented — and most presentations are not only poorly presented, they are in fact horribly presented — is an excruciating ordeal for all concerned and a cause of resentment in both the presenter and the audience. A well presented, useful presentation informs, and is appreciated by almost everyone. Giving great presentation may well by a gift — and is absolutely mesmerizing to witness — but giving good presentation is a skill: it can be learned.

I’m not going to try to teach you how to write a useful presentation: if you can’t acquire, organize, and summarize information, you have a much steeper learning curve ahead of you than a section in a robotics course can handle. But I can give some facts, attitudes, and practices I have found useful in the activity of giving good presentation.

A Presentation Is a Performance

A presentation is a performance with a purpose: that purpose is to transfer information to the audience to affect its future actions. The audience of the performance is human beings. Just as there are effective and ineffective methods of giving information to computer systems, there are effective and ineffective methods of giving information to humans. Giving information to humans is influenced heavily by three things: the human cognitive system, the human perceptual system, and human knowledge acquisition sequencing. Let’s review each of these in turn.

Human Cognitive Styles

You may have heard of “learning styles,” which were an attempt to translate cognitive styles into actionable information for teachers: the theory was that presenting material in the learner’s primary sensory modality would make the material easier to acquire. However, research strongly supports the idea that learning styles do not actually exist: it turns out humans are quite good at extracting information from any sensory input, and conceptualizing from that information in whatever way they conceptualize. But the evidence for cognitive styles is strong. It’s just that pre-translating information into a sensory modality you think associated with a cognitive style is about as useful as pre-digesting food: yeah, it can help in exceptional circumstances, but most folk don’t actually need that. The identified styles, and their implications, are:

(Remember the definition of a system as an arrangement of interacting elements that gives rise to emergent behavior? Systems are the kinesthetic equivalant of tactile sculptures or visual paintings or auditory symphonies or lingual poems and novels. This course is fundamentally about learning to build systems. Good thing all cognitive styles are in fact available to at least most, and probably all, persons.)

Traditional “teaching” techniques are tailored to lingual thinkers: traditional teaching consists of a torrent of words presented in lectures and books, with an occasional visual aid as a sop thrown to the visual thinkers. So-called “manipulatives,” for example, are an attempt to reach those with a tactile primary cognitive style, but are used only in very early elementary school. Why so little emphasis on non-lingual styles? Because ignoring them can be successful — those with non-lingual cognition can understand linguistic information, they just need to work harder — and because teachers have succeeded in getting through teachers’ colleges, which like most education is tuned to lingual thinkers, and so teachers themselves are or have been beaten into being lingual thinkers, and so typically do not actually understand non-lingual styles. But you’re not doing higher education, where you can (and if you adhere to traditional methods will) make 60% of the population do extra work over the course of a semester or year: you are giving a presentation to a broad and representative subset of humanity, and you have half an hour or an hour to do it. This is an exceptional circumstance: pre-digesting the food is worth it in this case.

Why, you may ask, are there such a variety of cognitive styles? Fundamentally, because there is no such thing as a standard issue human being: we vary from one another, a lot; although we like to pretend majority descriptive attributes are normative requirements for all, this pretence repeatedly fails. If there is an actual norm for humans, we have six or so millenia of recorded history showing that we are unable to identify it. But this variety is itself a good thing: after all, what does it mean when we say someone is “creative?” “Creative” means primarily thinks of different things than I do, or thinks a different way than I do. Kinesthetic thinkers, being somewhat rare, are over-represented in those widely regarded as “creative.” I suspect their actual creativity is no greater than that of everyone else, it’s just that it gets applied differently than that of everyone else, so kinesthetic thinkers make “unobvious” breakthroughs such as inventing Relativity or airplanes or mass production instead of “obvious” breakthroughs such as inventing poems or novels or paintings or chord progressions or syncopations or business plans or filing systems or hook and eye fabric. On the other hand, to a kinesthetic thinker, everyone else is creative: everyone else thinks differently than they do.

What is your cognitive style? You can get some hints from where you experience pareidolia. Pareidolia is your cognitive system imposing structure on random sensory inputs, and it is believed to happen in a manner closely associated with your cognitive style. You commonly see shapes in clouds? Possibly visual. You commonly hear low voices muttering in fan noise, or you can read signs in your dreams? Possibly lingual. You commonly hear music in fan noise? Possibly auditory. You are commonly struck by arrangements of elements of some type? Possibly kinesthetic. You get more than one of the above? Possibly a mixture. You get none of the above? Possibly you have never noticed what happens when you are drowsy (when pareidolia typically is most noticeable); or maybe you are some other cognitive style not yet recognized: it’s not like humans come with an owner’s manual and an options list. There may be four commonly recognized cognitive styles, but there must be more. There is almost surely a separate tactile cognitive style, because tactile (touch) senses are just or almost as basic as proprioception (the “where is my body and what is it doing?” sense). I am sure there is an olfactory cognitive style — there almost has to be, smell is “the most mnemonic of the senses,” the human olfactory bulb is just as complex as that of a bloodhound, the human olfactory cortex is larger than that of a bloodhound, so humans can smell at least as well as a bloodhound, it is just that most people (other than fresh non-smokers and organic chemists) typically disregard the sense of smell. But if tactile and olfactory cognitive styles exist, they are not yet recognized.

I frequently fall asleep to my fan playing me a symphony (or sometimes jazz, and very occasionally big band) or muttering far away and under its breath, my dreams are best described as featuring points with orientation vectors, and I could not possibly recall the color of someone’s hair (although I could probably sketch their hair style) after meeting them face to face: it just means my cognitive style is primarily kinesthetic with streaks of auditory and lingual, with very little visual. (I can see perfectly well, and my color vision is normal; I just don’t think in images: I think in networks of abstractions and arrangements of shapes.) People without an inner director and alternate camera angles are not defective: they merely have a different cognitive style than visual. People without an inner narrator are not defective: they merely have a different cognitive style than lingual. People without an inner sound track are not defective: they merely have a different cognitive style than auditory. People without an inner choreographer are not defective: they merely have a different cognitive style than kinesthetic. None of us are defective: we are merely human, humans come in lots of different flavors, and some flavors have even been recognized. C’est la vie; vive la différence!

In terms of giving a presentation, though, this variety of cognitive styles means there are four major distinct audiences you are presenting to at once, and just lecturing is going to reach less than half the overall audience (and lecturing in a mumble is going to reach exactly none of it). So, in giving a presentation:

It gets easier. Eventually, it even gets to be fun. And I say this as a confirmed introvert who feels constricted when there are more than four people in sight and loses the power of speech when introduced to someone new. (There’s a reason I wound up an engineer.)

Human Vision and Slide Design

Humans are typically regarded as having five senses, although over a dozen senses have actually been identified and named (such as balance and proprioception), and several other senses are strongly suspected. (For example, some persons are repeatably sensitive to magnetic fields, most everyone is sensitive to strong electric fields [although they typically do not recognize the sensation as indicating a threat], and with training sighted persons with organic eye lenses can see light polarization. Sighted persons with artificial eye lenses can see the near ultraviolet, an interesting factoid. I’m told it looks bluish white.) In order of seniority, the senses are very likely touch, smell, hearing, and vision, with taste and proprioception somewhere in there around touch. In order of distance of perception, the senses are vision, hearing, smell, and finally taste, touch, and proprioception. But even vision and hearing come to us from very ancient armored fishes, along with such things as overall bilateral symmetry; a spine; the dorsal/ventral (back/front) asymmetry; the one head, two fore limb, two rear limb body plan; a specific set of internal organs; and more. The data input channels to this whole “animal” concept have been more or less stable for a very long time, which means they are both valuable and more or less adequate.

Humans, along with all the other primates, and possibly along with everything else with a cortex, in fact have two visual systems. The optic nerves go to the brain stem, and there vision is interpreted by the primitive visual system; information is then relayed to the visual cortex, at the rear of the brain, where far more elaborate processing happens. We are aware of the perception happening in the visual cortex. We are not aware of the perception happening in the brain stem, because we don’t live in the brain stem, we live in the cortex — but experiments (mostly on monkeys) have shown there is recognition of lines and their orientation, recognition of circular shapes, rough positioning in the visual field, and recognition of direction of movement happening there. This primitive visual processing happens much faster than our conscious perceptions, and is responsible for such things as flinching away from sudden movement and the blink reflex for things heading towards our eyes. The primitive visual system appears to be monochrome (black and white) and particularly rich in vision’s periphery (which, if you know about the distribution of rods and cones in the retina, comes as no surprise). Atheletes such an fencers and martial artists basically program carefully planned reflexes into the brain stem based on this primitive visual system: their reactions must be faster than a trip through consciousness would permit. (A trip from eye, through consciousness, out to motion typically takes about 350 milliseconds; a “reflex tester” involving grabbing an unexpectedly dropped vertically hanging stick at your local children’s science museum can tell you more, although not about actual reflexes.) In computer terms, fencers and martial artists are putting processing out where the data is, rather than waiting on bringing data to the processor.

Now this is fascinating, but what does it have to do with giving presentations? Just this: two of the things we inherited from the armored fishes are the single lens structure of the eye, and the optic chiasm. The single lens structure of the eye means the left side of the visual field is presented to the right side of the retina, and vice versa; and the optic chiasm means the right side of the retina from both eyes is presented to the right side of the brain, and similarly for the left. The only animals so inbred as to have lost the optic chiasm — white tigers and (in the 1960s through 1980s) blue point Siamese cats — have severely impaired visual perception, so while we may not understand why an optic chiasm, it is apparently a big deal.

Which would not really matter, except that humans (apparently uniquely) have hardware assist for language (called Broca’s area), and it is almost always in the left hemisphere of the brain; this is part of human hemispheric specialization. Hemispheric specialization in turn means that language and temporal processing is done preferentially in the left hemisphere, and visual and gestalt processing is done preferentially in the right hemisphere, as split brain studies of persons with corpus callosum impairment have shown. This is preference, not raw capability, as neuroplasticity frequently permits significant recovery from deficits resulting from brain injury. In some persons the division of preference is reversed. There is also speculation the preferential processing is related to handedness, which along with Broca’s area and hemispheric specialization appears to be unique to humans.

All of which means text goes on the right side of the slide to be perceived by the language (left) hemisphere of the brain, graphics on the left side of the slide to be perceived by the gestalt (right) hemisphere of the brain. So this rule of thumb — visual on the left, text on the right — might be science or might be pseudoscience, but it is really common advice, which I dutifully repeat here, along with some explanation as to why it might be plausible.

Other properties of the human visual system inform other aspects of slide design. Our vision fatigues rapidly, on the order of seconds: we simply quit seeing if the image on our retinas does not move. We adapt to this with saccades, where we voluntarily focus on different aspects of the scene, and micro-saccades, where the eye jerks involuntarily to refresh retinal response at edges in the visual image. (Micro-saccades also appear in other animals with foveal vision, where there is a high-resolution spot in a field of low resolution peripheral vision. It appears to just come with the territory.) Edges are very important to visual processing: to a large extent, our vision interpolates from edges; uniform areas are by and large not actually seen, just implied. This in turn means contrast is necessary for us to actually see: contrast in luminance, or contrast in color. And that in turn means your fonts must be large enough to be seen, wide enough that interior letter detail can be recognized, and contrast with the background. In other words: avoid Times and Arial/Helvetica, these are semicondensed fonts and do not project well.

Of the spectral colors, we see yellow and green best, blue poorly overall, and red very poorly in our central vision. Blue on black is seriously invisible to a lot of people, as is red on black to a different lot of people. Red and green use the same visual channel, and a boundary between a strong red and a strong green is perceived as vibrating: avoid this. This appears to be because humans do not actually see the color red: persons with typical trichromatic vision actually see only blue, green, yellow (actually chartreuse), and overall luminance. Red is perceived based on the differences in responses among the color perceiving cone cells and the luminance perceiving rod cells in the retina. As far as our eyes are concerned, red isn’t a color: it is luminance in the absence of blue and green. Our overall detail resolution for blue is about 20% of our detail resolution for green and yellow, because of the proportions of color specialized cone cells in our retinas; our detail resolution for red, in our central vision, is also low because cone cells (that don’t respond to red) are particularly rich, and rod cells (that do respond to red) are particularly poor, in our central vision. We simply do not have good visual detail resolution for blue and red: that’s just human physiology and we need to adapt to it. In other words: your text and diagrams must be white, black, green, or yellow; avoid blue and red.

Color blindness is a thing: if you differentiate two things by color you have to differentiate by something else as well: font weight, font style, one or the other in a box, whatever. But color harmony and dissonance is also a thing: look up the color wheel and seriously consider complements, triads, tints, shades, and tones when you are deciding on a color palette for your presentation (and learn about HSL and HSV, instead of RGB, color specifications). The need for contrast also means that if you use a dark slide background, use white or at most a slight tint in the diagrams and text; if you use a light slide background, use a black or very dark shade in the diagrams and text. In either case, while your title slide can use a dramatic image and color scheme, keep the other slides subdued: that dramatic red slash across a full-color photograph will be impossible to read over. Although it’s difficult to give advice in something so close to art, I suspect about the most dramatic background one can carry off successfully in a slide template is an image at 5% to 10% opacity over a solid color or gentle color gradient of either light tints or dark shades: anything more gives too many edges and too much visual confusion.

I also have to warn against intrusive decoration on your slides. A color gradient or washed out image background, and template design elements such as colored divider bars and bullets, look polished, but random arbitrary decoration is just distracting. I have seen an entire audience of a hundred C-level executives get completely lost in a presentation when whomever did the slides decided to put “a touch of color for visual interest” into a text heavy slide (already two bad choices). The touch of color was a vertical slice of a much larger image that had been used in an ad campaign; the slice consisted of a field of orange with brown and black lines running through it. But because it was a slice with all the context cut away, it didn’t actually look like anything. Was it an aerial photograph of a river in a desert? A photomicrograph of part of a computer chip? A chemical reaction? A damaged diffraction grating? Irridencence from some very thin layer of something? Light transmission through some mineral with some sort of inclusion? Because of the subtle shading, it was obviously a photograph. But a photograph of what? And why was it on the slide? That “touch of color” was the only thing any of the C-level folk remembered about the entire presentation and the only thing they talked about afterwards. The impact of the entire presentation was lost to a single decoration on a single slide. Don’t do that.

Yes, text is easy to produce: you type it into a computer. Slide transitions — where one slide fades into another or its pieces are replaced with others — are also easy: you just pick one from the menu. (Avoid slide transitions. Fades and disjoint movement in the visual field causes alarm, not interest: that’s the brain stem saying WTF.) Cheezy clip art is easy to find, easy to use, and typically does not meet the need of communicating the point you are trying to make. That they are easy doesn’t make walls of text, or slide transitions, or clip art, good. You must appeal to all cognitive styles, and account for all human perceptual glitches. A presentation is not a document, it is a spatial and temporal communication.

If it’s on the screen, it must be meaningful and relevant. Asides are for the voiceover.

Sequencing Preferences

There are two common ways of acquiring new knowledge, top down and bottom up:

Some people best acquire information when it is presented top-down (generalities to details, deductive or analytical), some when it is presented bottom-up (details to generalities, inductive or synthetical). These each get the job done and are equally valid methods of learning. For example, in presenting information about earth movers, you could move from the general “we need to move a lot of overburden” to the specific of “large powerful machines with treads and blades or buckets;” or you could move from the specific “treads grip the earth and allow powerful transverse and vertical forces to be applied” to the general “this allows us to quickly remove large quantities of overburden.” I don’t know of any actual studies as to what proportions of people need each approach, but everyday experience will tell you that a large fraction of people need one or the other or they simply will not “get it.” So you have to provide both.

So how can you possibly provide two different orders to the material in a single arrangement? Well, the public speaking rule of three comes to the rescue here:

This rule of three does not mean say the same thing three times. It means the overall presentation should be structured as an overview (that goes one way), detailed information (that goes the other way), and finally a summary or conclusion (that goes the other other way, or the same way as the overview). This hits both knowledge acquisition sequences. The overview typically comes along with the presentation table of contents slide, if you have one: having a table of contents slide typically means the overview is presented big picture first, which implies the body should be details first. The top-down and bottom-up alternation rule also suggests that if you have a subject where the detail discussion must be top-down (assuming there are such subjects), a table of contents is a sub-optimal overview slide. Perhaps a tag cloud, or a mind map, would be better in such a case.

Now, you will have the urge to structure the detailed information either general to specific, or specific to general. This urge is the result of your preferred knowledge acquisition style: “of course it should be structured this way, that’s what makes sense.” And that is what makes sense — to you. The optimal structure actually depends on the audience: are they “big picture” people (typically senior managers juggling a broad spectrum of concerns), “detail” people (typically line workers or line supervisors with sharply delineated responsibilities), or something in the middle (typically middle management)? Feel free to engage in stereotyping about your target audience with regard to presentation sequencing: it’s not like there is any actual data in this area. Just beware of stereotyping turning into contempt: your audience is not dumb because you think they might be different than you. They in fact are knowledgeable and skilled in their field, highly motivated, and interested in getting better — if they weren’t, they wouldn’t be in your audience, now, would they?

A great many people are also helped by analogy. This is like that in some way, so what helps with the “some way” in the that can be expected to help in the same way with the this. For example, spoons nest tightly, and need to be separated in the dishwasher so all parts of them get clean. Dishes also nest tightly, so need to be separated in the dishwasher for the same reason. Spoons can be separated by putting them going different directions, one going up and one going down; but dishes are typically rotationally symmetrical, so they have to be separated by distance instead. So fluff the spoons and put the dishes in with half an inch or so between them so the water can get in. (I also have to give credit here: the phrase “fluff the spoons” is due to a poet acquaintance, and I am intensely jealous.) Reasoning by analogy is suggestive and helps provoke creativity, but is not a guarantee of correctness (sympathetic magic doesn’t actually work); but explaining by analogy, if the analogy is valid, can be quite helpful.

Overall Presentation Structure

A presentation has a traditional overall structure and flow, and this structure and flow is echoed in the slide deck, the sequence of slides to be displayed. As noted above, the overall structure is introduction, details, summary, in that order. Additionally, presentations typically have a preface: an introduction to the presentation itself, which is different than the introduction to the subject matter of the presentation. So overall, the structure of the presentation, and thus of the slide deck, is as follows:

And then the presentation is over, and look! You survived.

Time the presentation so five to 10 minutes are available at the end for questions, bio-breaks, coffee refreshes, and so forth.


Let’s talk about what you say when giving a presentation, or, rather, how you say what you say: the voiceover. This is where most of the information transfer happens; and supposedly very little of what you say is in fact what you say. There is a famous study that says 7% of communication is words, 38% is tone of voice, and 55% is body language. Well, the study actually doesn’t say that, it is just interpreted as that; and that interpretation is wrong. What the study actually says is that written text is seriously impoverished in emotional cues, something I doubt anyone seriously disputes. If text weren’t so impoverished, there would be no poets to overcome the impoverishment and no poetry criticism to figure out what the poets mean. (“Criticism” in this context does not mean pointing out flaws; it means judging merits. Criticism can be quite favorable.)

Communication has both denotation (what it means) and connotation (what it calls to mind). Connotation is very powerful: it’s the difference between being principled and being obstinate, between a slip-up and a betrayal, between a butt dial and a booty call, between a neighborhood and a ghetto, between an aroma and a stench. Humans are emotional, there’s no way around that; and connotation is the set of emotional cues that go along with information. Connotations change over time: when I grew up, “fabulous!” was a synonym for “wonderful!” and I’ve had to retrain myself because, well, they don’t mean the same thing now. In addition to word choice, tone of voice is a rich channel for emotional cues: enthusiasm, acceptance, indifference, resentfulness, ridicule, and negation can all be conveyed by tone of voice. Body language, too, is a rich channel for intensity (and to some extent type) of connotation. The actual meaning of a communication is arguably whatever the receiver of the communication gets from it; make sure what the receiver gets is what you intend.

Most people talk at 90 to 180 words per minute. You are not talking, though: you are giving a presentation. When presenting, you need to slow down, and I mean seriously slow down: 60 to 100 words per minute is about the fastest you should go. This does not mean one word every second like a metronome: it means talk loudly, slowly, and distinctly; enunciate precisely; and use punctuation freely. Most verbal punctuation is pauses of various lengths or changes in intonation. Fifty to 100 milliseconds and a slight drop in pitch is quotation marks; 200 or 300 milliseconds is a comma; 500 to 750 milliseconds is a period; rising pitch is a question mark. Facial expressions are also punctuation: both eyebrows raised is a question mark, a single eyebrow raised is skepticism, both eyebrows down is concern, eyes wide open is alarm, and so forth.

English is fascinating and unique in that it is three languages at once: it is German and Danish at the base (from the Angles and the Jutes), with an overlay of Latin (from the Romans), and a further overlay of French (from the Normans). (English also mugs other languages in dark alleys and rifles through their pockets for loose vocabulary, but most of it is from these three.) The Germanic and Danish base words are short and generally monosyllabic; the Latin words are long and polysyllabic; the French is intermediate. “Gut,” “torso,” “abdomen:” German, French (actually Italian in this particular case), Latin. If your audience is native English speakers, keep to the German, Danish, and French words, which are most common. If your audience is English as a second language speakers, keep to the French and Latinate words, which are most likely to be cognates of words in their primary languages and, being longer, are easier to hear and keep track of. With a severe language barrier, you may need to slow down delivery even more and pause after every phrase.

Meter — the thing that makes poetry, poetry — matters. Latinate words typically use three-syllable feet like dactyls (cir·cum·vent dom·i·nant par·a·digms), while French words typically use two-syllable feet like trochees (child·ren pro·test night·time cur·fews) and iambs (be·hold ef·fete re·sults), and surviving Germanic and Danish words typically are stressed as nouns and verbs and unstressed as function words (run free, my friends). Be aware of your meters: you don’t want to lull your listeners to sleep with a solid minute of dactyls, or get them to want to join the chorus with a minute of iambic trimeter and tetrameter quatrains (also called, for good reason, “hymnal stanza”), and you also don’t want to be continually barking with spondees (halt thief, stand fast). (Actual Old English verse used accentual half-lines and interior alliteration, rather than feet and inter-line rhyme. The more you know!) Your voice is a musical instrument with a two- to four-octave range and exquisite volume, timbre, and tempo control: use it.

Audience Engagement

Be very wary of giving a presentation someone else wrote, especially if there is no report to go along with it. Whoever wrote the presentation probably doesn’t know how to write, or give, a presentation, and you’re stuck with a hideous mess of walls of text because someone mistook Powerpoint for Word. There are entire teams whose only job for three months at a shot is writing one keynote presentation for a CEO to give. Writing a presentation is a skill; writing a presentation for someone else to give is an art, and a specialty one at that. But that’s a rant for another time.

The secret of success is sincerity. Once you can fake that, you’ve got it made.

— variously attributed to Jean Giraudoux, Groucho Marx, and George Burns

You need to have had the thought process going into the slides in order to credibly present the result; without at least having collaborated in the creation, you are not performing, you are acting, and that is a different (and far more difficult) skill set. The thought process going into the slides can sometimes be acquired by studying the report, but the familiarity with the topic of having done the research is also critical. There’s a reason “talking heads” that regurgitate a script someone gave them are not well respected. Your audience can tell whether you know what you are saying is accurate and complete. Don’t try to fool it. You might be able to bluff through the presentation itself, but not the questions at the end. It never works, don’t even try. In school, handing in a bought term paper might get you a B or an A, while stumbling through a bought presentation might get you a C; but in business, a presentation someone else wrote will not get you the sale, or the funding, or the glowing performance review and raise. The presentation will be perceived as mediocre at best.

So what do you do when ordered to present a canned presentation? You sigh, give it your best shot, and don’t expect much from it. Sometimes being a mediocre talking head is your job.

A presentation’s audience is people, humans. Humans are biological entities. Biological entities have basic biological needs: no one is going to pay attention to the presentation if they need to pee right now or if they are so hungry they hurt. Maslow’s hierarchy of needs is a model of human needs which has largely been validated (as much as any social science model can be validated) and which is useful is this context. From the bottom (most physical) to the top (most spiritual), these needs are:

Presentations are typically addressing information needed to inform effective action. Effective action is a type of competence; information yielding effective action is a form of knowledge, a satisfaction of curiosity; effective action is in service to organizational or personal goals, a grander purpose than simple existence. So presentations are aimed squarely at the middle of Maslow’s hierarchy of needs, right at the boundary between deficit needs and growth needs. Which in turn means that any unmet needs lower in the hierarchy — here earlier in the list — will distract from the effectiveness of the presentation. In other words: trying to teach the finer points of double entry bookkeeping to a starving, shivering refugee isn’t going to be successful.

Some of the people in the audience will be undergoing divorces, or having their mortgages foreclosed on, or know their mother is dying, or have been told they are being laid off next week, or have just learned they have cancer, or having some other major dislocation in their security. We can’t do anything about that. But we can make sure the fire alarm isn’t blaring, or the rain isn’t blowing through the windows, or the air isn’t stifling, or the audience knows where the bathrooms are, or the audience knows where the coffee and water is. There is a reason why, in Robert’s Rules of Order, a point of “privilege of the assembly” (“we need to close the windows,” “we need to take a bathroom break,” etc.) can interrupt any other question or deliberation. These basic needs must be met before anything else can be done.

So, assuming the basic needs are met, your audience can pay attention to the presentation. Assuming you do the pre-digestion into sensory modalities, and design the slides for human perception and cognition, and have a reasonable outline and defendable thesis, your audience can understand the presentation. They can pay attention and understand. So what other barriers are there to the audience accepting the information and informing their actions? There are two big factors: organizational culture and defensiveness.

Organizational culture is one of those things that is typically invisible from the outside, and, like water is to fish, just the way things are from the inside. But a strong organizational culture can be relatively easily identified:

Typically a few minutes’ chit-chat with the presentation’s sponsor will be enough to get a good grasp on the organizational culture, even if the sponsor has never heard the phrase and never thought about it. Your presentation manner must be in line with the organizational culture. There is no such thing as a target of opportunity in a hierarchy culture: those are possible opportunities for future consideration subject to strategic positioning. There is no such thing as acceptable performance in a market culture: there are met targets, or missed targets and recovery plans. There is no such thing as a directive in a clan culture: those are available opportunities for synergistic activity synchronization and harmonization. There is no such thing a legacy or compatability in an adhocracy culture: those are proven opportunities for further innovative activity. Yes, it’s stupid. But also yes, it’s important. Read up on organizational culture and know what you need to target and how you need to refer to things to be acceptable to your audience.

All of these cultures are functional: they are stable, and they work, regardless of whether they are to your taste. One can be more or less effective than another, depending on the environment, but they are typically all adequate. But there are also dysfunctional cultures. For example, if the organization has cliques, or punching bag individuals or groups that are inherently Wrong, or annointed individuals or groups that are inherently Right, the organization is a diseased middle school and is straight-up doomed. This organizational syndrome, and the leadership attributes that give rise to it, is described (sugar coated in humor, but still insightful) in Parkinson’s Law as “injelitance.” It doesn’t matter what you do for, with, to, or about an organization with a dysfunctional culture: it is simply doomed. Don’t worry about how you are received there: you cannot affect your reception or acceptance in any respect, and it really doesn’t matter anyway, they’ll be gone in a few years.

Defensiveness is part of some organizational cultures, but is also simply a native human trait. Humans are competitive, and many organizations foster competitiveness among staff in an attempt to create organizational competitiveness in the environment. (This is actually typically counterproductive, but then, many things management does when they mistake organizational attributes for personnel attributes are counterproductive. Staff is not actually thinking about how best to do the job when their goal is to game the metrics or outshine that rival.) This in turn means the default approach to a communication is to not listen to what is meant, but to what is said, with the goal of finding some way to attack, minimize, or ignore the message and to retain the current understanding and status quo. Basically, everyone is primed to win the conversation: “active listening,” where the goal is to understand rather than win, is sadly both unpopular and uncommon. Cognitive and intellectual defensiveness is probably the greatest single barrier to communication you will encounter. There is a reason Covey’s “Seek first to understand, then to be understood” has been identified as a habit of people who are uncommonly effective: the habit itself is both effective and uncommon.

In giving a presentation, you want the audience to lower the defensive barrier: to hear and to understand what you are meaning, not to figure out how to respond to what you are saying and defend their current understandings. The audience has to do this voluntarily: you can’t make them do it, you can only invite them to do it and show that it is safe. You want to ingratiate yourself with the audience: to have the audience to accept you as “one of us,” or at least “a friend intimate enough to know our concerns and sympathetic enough to appreciate them,” to give credibility to what you are saying, but without sacrificing the aura of expertise you have by virtue of standing at the front of the room in front of a projector screen. Seek commonality with the audience: it’s there, it helps. It helps a great deal.

Probably the best way of becoming non-threatening is a conversational tone. This is a style of being, a manner of behaving, not a particular behavior. You are a friend; the audience is your friends; you are just telling your friends about something you happen to know and they happen to not. It’s fascinating, isn’t it? Or at least interesting. We’d like to do this in response, but this fact over here means that would be risky, which is a shame. But this fact over here means we can respond this other way, which is almost as good. Isn’t that convenient?

So define your technical terms, and repeat the definition the next two or three times you need them: “it’s a system, an arrangement of components that exhibits emergent behavior, that is, behavior that the arrangement has that none of the components have by themselves” is a phrase you’re probably sick of by now, but you aren’t going to forget what “system” and “emergent behavior” mean, are you? Keep the words casual and conversational: this is a conversation, not a formal document: say “kids and siblings and parents” not “first-degree blood relatives;” say “it gets hotter” not “its temperature increases;” say “water” instead of “aqueous carrier.” Appeal to every day experience: we all know what a door is, we all know what dogs are, we all know that a door is what a dog is forever on the wrong side of, so if your semipermeable membrane lets some things through and not others you have the perfect explanation of what’s going on: you’re going to hold the door open for the dog but not for the skunk, right? Appeal to the senses: a prism splits light apart by color, into what is called a spectrum, just like a rainbow; and there is invisible light on each side of the visible light part. This was proved by finding chemical reactions that happened faster or slower depending on what color light shined on them: the reactions that liked red liked the black space right next to red even better, and we call that invisible light infrared; the reactions that liked blue liked the black space right next to blue even better, and we call that invisible light ultraviolet.

On the other hand, beware of idioms. Firstly, they don’t translate, so any language barrier will become a language wall. Secondly, some people will never have heard the idiom and may be offended. I once crashed and burned in a job interview because I described my software development group as the “red-headed step child” of a manufacturing organization; the interviewing manager got very indignant and said “I have a step child!” Well, yeah, and at the time I had three, and the idiom is older than Shakespeare; but the interview was over right then and there anyway. You do not want the presentation equivalent of that.

Related to idioms is jargon. Every field has jargon: in particular, your field has jargon. The audience also has jargon. The two jargons frequently use the same words for different things. In systems, a “signal” is an indicator of some type, and can be as trivial as a voltage on an IC pin or a single bit in memory. In a navy, a “signal” is a thing that involves Admirals and encryption clerks and entire fleets, and is never trivial. In operations research, there is a “trans-shipment problem,” where multiple products are distributed to multiple destinations in multiple steps from multiple sources. In at least one shipping company, a “trans-shipment problem” is sending the product to the wrong destination. You will stumble across miscommunication related to jargon. There’s not a lot you can do about clashing jargon, just be prepared to use alternate words when you discover this happening. Adopt the audience’s jargon, don’t try to force your own.

I personally also like to use humor in my presentations; but then, I use humor in my conversation, so it’s on-brand for me. Humor is hard to define, but one definition is “the juxtaposition of incongruities,” a totally inadequate definition. On the other hand, juxtaposed incongruities — we park on a driveway but drive on a parkway — can be humorous and are typically safe, except in a hierarchy culture. (Humor is forbidden in a hierarchy culture.) Humor is a double-edged sword, and can help or hurt, so be wary. And never make any individual or group, other than yourself, the butt of a joke: that’s a really good way to make an instant opponent out of someone who could have been be an ally.

Actual knowledge; meeting needs; commonality in attitudes and expressions; non-threatening; conversational tone; avoiding foot-in-mouth disease. These are the keys to audience engagement. And audience engagement is the key to information acceptance and use.


An army marches on its stomach.

— attributed to both Napoleon and Frederick the Great

There are few feelings to compare to that of discovering you have flown a thousand miles to a meeting and forgotten to bring your presentation. I do not recommend experiencing this feeling this first-hand.

Logistics deals with the procurement, transportation, distribution, maintenance, and replacement of matériel, facilities, supplies, and personnel. A whole lot of things have to go right for you to actually give a presentation. Part of your job as a presenter is to make sure things still go right, even if something goes wrong. Even if a lot of somethings go wrong. The logistics of the presentation are all the things you put into place so that if anything reasonably imaginable goes wrong, the presentation still goes right. I can’t give you a procedure because I can’t tell you what will go wrong for you, but I can give you the advice I wish someone had given me when I started. Most of the following is irrelevant at the beginning when “the venue” is the room down the hallway, but it gets more relevant the more you do this. Here it comes:

All the above goes in your carry-on bag, that you wear with the shoulder strap cross-chest to the far shoulder and that you staple to your chest, because it all must arrive with you. Yes, it’s heavy; but it’s your carry-on and you carry it, because you must have this with you. You can put it all in checked luggage on the way back. If you’re flying and particularly if you’re going international, don’t take your actual laptop, take a $200 nettop that has only what you need on it to give the presentation and has never been used for social media. If you go somewhere like China or a former Soviet country or the middle East, you’ll want to DBAN and reformat the disk and reinstall from distributions when you return. (Don’t ask why, just do it.)

Have a checklist, an actual physical piece of paper, and make actual physical checkmarks as you pack your carry-on. Double check the checklist against your carry-on. Then check your checklist against your carry-on again when you arrive where you are going, and work out what panicked arrangements you need to make because things disappeared or broke en route.

One of the interesting things about business travel is that it lets you form first-hand and intimate impressions of far away places. For example, Manhattan is a powerful argument for thermonuclear warfare: 50 or 100 megatons would do the place wonders. England as a whole is a great argument for global warming: 200 feet of sea level rise would be just the thing for it. But then I wouldn’t be able to live in Denmark or Wales. Alas.

“There is no such thing as luck: there is only adequate or inadequate preparation to cope with a statistical universe.” The universe is a real bitch sometimes. But the show must go on, and good logistics lets that happen.


There are two types of handouts: copies of the slides (with room for notes) that you hand out at the beginning of the presentation, and formal documents repeating everything in the presentation and giving sources, detailed reasoning, and detailed information that you hand out at the end of the presentation. Copies of slides are common and useless, but formal documents are uncommon and invaluable. Copies of the slides are useless because the slides, by themselves, are useless: they are the structure of a presentation, not the presentation: the presentation is a half-hour or hour-long performance. The slides are evanescent and largely meaningless out of the context of the presentation itself. Copies of slides might serve to remind one person, the attendee, of the topics addressed, but rarely of the insights gained. A formal document, typically structured as a report, has a durable, stand-alone existence and can be used by the audience member to proselytize within their organization.

You write the handout at the same time as you write the presentation slides, create the visuals, and write the presentation script. (Do not attempt to read the script when presenting; you will come off as stilted at the best, as condescending at the worst. The last time the audience members were read to, they were five years old.) Read the script out loud — to yourself, or to a friendly audience, not to the target audience — at least four or five times, until you can recall at least most of it offhand; then leave it at home. At most have index cards reminding you of the points you want to make. If you forget something important, oh well, there’s always next time. Cover everything in the handout you covered in the presentation, but play it straight: this is a formal document, probably a report: no jokes, and asides belong in footnotes or sidebars, or get omitted entirely. Cite your reference materials. A major purpose of the presentation is to position the handout as relevant, authoritative, and actionable.


Preparing a good one-hour presentation takes about three weeks of hard work: about a week for researching the problem, surveying its solutions, figuring out superiorities and deficits of each, figuring out what to propose, and figuring out business processes that avoid or mitigate the deficits of the direction you propose; a half week for outlining and boiling down what you want to say to bullet points; a half week for the slides and creating the visuals; a half week for the 10- to 15-page report handout; and a final half week for choreographing, rehearsing, and preparing your spontaneous verbal asides. And that is after you’ve become proficient: double the time estimates for your first few presentations.

But don’t despair: your first presentations aren’t going to be one hour presentations to a bunch of C-level executives of Fortune 50 firms with not only your paycheck but your career on the line. They are going to be ten minute, five or six slide, presentations to your coworkers or classmates, about something you already know; and you can knock one of those out in an afternoon. Logistics will consist of hitting the bathroom on your way to the meeting. You will probably be even able to keep lunch down that day.

Capitalize the presentation preparation: retain sources for the slides and script and choreography and handout, make copies of the source material you referenced (actual copies, PDFs or scans, not just URLs), and put them all in your repository. Your work group should have a library of presentations: put it there, too. You will get to use all these again, either as-is or with minor tweaks.

A useful presentation, well delivered, is absolutely convincing. Not because it is well delivered: the delivery is just to get the audience to pay attention to and understand the content. A presentation is convincing because it is obviously relevant, both topically and organizationally; because it is obviously authoritative, from someone who knows the problem, all the solutions, and the implications of and trade-offs among them all; and because it is obviously actionable, something you can start using now. You will know you have done not just well but spectacularly well when the audience asks for you, specifically you by name, for future presentations.

Giving a presentation is like tying your shoelaces: it is just a skill, and a skill is a capability that you can learn. You can do this.

UI Implications (An Aside)

Although not actually relevant to giving presentations, one of the more interesting, at least to us computer types, sets of implications of the cognitive styles and visual perception discussions is what it means to UI design. The visual aspects of UI elements — color, font, luminance contrast, and so forth — are critical to a graphical user interface. Cognitive styles are also important: some people depend upon the text; some the colors; some the shapes; some the time dependent changes in the screen (such as animated icons, or appearance and disappearance of UI elements); some the sounds; some the voice cues. Does your UI have all these elements, to address the needs of all of your user base?

Imagine the line of business application you use every day had a user interface consisting entirely of randomly placed (and occasionally relocating) animated icons and two- or three-note musical passages from various instruments. Useless, you say? Incoherent, you say? Insane, you say? Yet that is exactly what your menu-driven application looks like to someone whose lingual processing is subordinate to another cognitive style. Want proof? Change your UI language to Chinese or Thai or Devanagari; now try doing something with your favorite application. That’s odd, I thought you said you knew how to use that program. Use color and fonts as an information route, not a decoration; use icons in addition to text; have a set of both static and animated icons that the user can choose to use; group information; have tones or audio effects acknowledging or identifying the operation; make all these cues and information channels redundant with one another, and have which sets of interface effects used selectable by the user. If your UI toolkit gives you things like tooltip and screen reader support, use them; if not, why are you using a UI toolkit that doesn’t support interfacing with actual users? Come on, at least give your users a chance.