[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:01.34,0:00:08.72,Default,,0000,0000,0000,,The key innovation of the graphic user interface is that input is performed directly on top of output.
Dialogue: 0,0:00:08.72,0:00:14.44,Default,,0000,0000,0000,,Today, we’re going to explore what makes an interface easy, hard, or “natural,”
Dialogue: 0,0:00:14.44,0:00:21.19,Default,,0000,0000,0000,,and we’re going to do it by starting with something really simple: a measuring cup.
Dialogue: 0,0:00:21.19,0:00:25.04,Default,,0000,0000,0000,,It has a user interface: it’s got label readout here.
Dialogue: 0,0:00:25.04,0:00:28.92,Default,,0000,0000,0000,,There’s a task: Fill up a liquid to a desired amount.
Dialogue: 0,0:00:28.92,0:00:33.59,Default,,0000,0000,0000,,So, how might you be able to improve this standard measuring cup design here?
Dialogue: 0,0:00:33.59,0:00:35.87,Default,,0000,0000,0000,,What kind of things can you think of?
Dialogue: 0,0:00:35.87,0:00:39.36,Default,,0000,0000,0000,,OXO is a company that sells kitchen utencils.
Dialogue: 0,0:00:39.36,0:00:45.87,Default,,0000,0000,0000,,At the Gel Conference in 2008, OXO’s Alex Lee talked about their measuring cup:
Dialogue: 0,0:00:45.87,0:00:48.86,Default,,0000,0000,0000,,The first prototype came unsolicited in the mail;
Dialogue: 0,0:00:48.86,0:00:54.61,Default,,0000,0000,0000,,it inspired them to go out into the field and ask people about problems with their measuring cups
Dialogue: 0,0:00:54.61,0:00:56.81,Default,,0000,0000,0000,,and suggestions for improvements.
Dialogue: 0,0:00:56.81,0:01:02.92,Default,,0000,0000,0000,,They got things like: “It’s sometimes slippery” or “The handle gets hot”.
Dialogue: 0,0:01:02.92,0:01:05.86,Default,,0000,0000,0000,,Nobody complained about the measuring part;
Dialogue: 0,0:01:05.86,0:01:11.36,Default,,0000,0000,0000,,but, when they watched people measure things, they would do this:
Dialogue: 0,0:01:11.36,0:01:13.78,Default,,0000,0000,0000,,Grab some liquid;
Dialogue: 0,0:01:13.78,0:01:18.46,Default,,0000,0000,0000,,Pour it in;
Dialogue: 0,0:01:18.46,0:01:23.33,Default,,0000,0000,0000,,Hold it up;
Dialogue: 0,0:01:23.33,0:01:26.20,Default,,0000,0000,0000,,Pour some more in;
Dialogue: 0,0:01:26.20,0:01:29.04,Default,,0000,0000,0000,,Hold it up;
Dialogue: 0,0:01:29.04,0:01:31.20,Default,,0000,0000,0000,,Pour a little more;
Dialogue: 0,0:01:31.20,0:01:34.96,Default,,0000,0000,0000,,There we go!
Dialogue: 0,0:01:37.46,0:01:39.95,Default,,0000,0000,0000,,This stuttered-step measurement seems kind of inelegant,
Dialogue: 0,0:01:39.95,0:01:48.97,Default,,0000,0000,0000,,so, to address this, OXO released a design with a clever insight: The numbers are visible from above.
Dialogue: 0,0:01:48.97,0:01:53.68,Default,,0000,0000,0000,,This provides continuous interactive feedback on your actions.
Dialogue: 0,0:01:57.60,0:02:02.57,Default,,0000,0000,0000,,Pour once; and when you get to the right level, you can see it directly and stop.
Dialogue: 0,0:02:03.92,0:02:08.16,Default,,0000,0000,0000,,It’s a great design in lots of ways, but there’s still some room for further improvement.
Dialogue: 0,0:02:08.16,0:02:14.30,Default,,0000,0000,0000,,For starters, the numbers that are written are sideways from the reader’s perspective.
Dialogue: 0,0:02:14.30,0:02:19.61,Default,,0000,0000,0000,,Not a huge deal, but still, it’s kind of like when you have to tip your head to look at a table.
Dialogue: 0,0:02:19.61,0:02:24.43,Default,,0000,0000,0000,,And also — some of you may like this, but I’ve always found this ridge here to be a little inelegant:
Dialogue: 0,0:02:24.43,0:02:30.25,Default,,0000,0000,0000,,This feels like a medical device more than something that belongs in the kitchen.
Dialogue: 0,0:02:30.25,0:02:37.22,Default,,0000,0000,0000,,And, when I went to the grocery store today, I actually found this measuring cup by Pyrex:
Dialogue: 0,0:02:37.22,0:02:44.47,Default,,0000,0000,0000,,It takes the insight from the OXO measuring cup — that you can measure from above —
Dialogue: 0,0:02:44.47,0:02:46.35,Default,,0000,0000,0000,,and improves upon it in two ways:
Dialogue: 0,0:02:46.35,0:02:52.52,Default,,0000,0000,0000,,The first is that the numbers right here are readable from the reader’s perspective.
Dialogue: 0,0:02:52.52,0:02:58.03,Default,,0000,0000,0000,,Hold it in the right hand if you want ounces, or in your left hand if you want millilitres.
Dialogue: 0,0:02:58.03,0:03:03.72,Default,,0000,0000,0000,,The second is that, for me at least, this design is a whole lot cleaner and nicer-looking.
Dialogue: 0,0:03:06.84,0:03:10.13,Default,,0000,0000,0000,,So, in this humble story of a better measuring cup,
Dialogue: 0,0:03:10.13,0:03:16.08,Default,,0000,0000,0000,,Alex Lee at OXO has provided us with four important lessons about human-centred design.
Dialogue: 0,0:03:16.94,0:03:19.78,Default,,0000,0000,0000,,There’s a common story that the carmaker Henry Ford once said,
Dialogue: 0,0:03:19.78,0:03:26.40,Default,,0000,0000,0000,,“If I asked people what they wanted, they would have said ‘a faster horse.’”
Dialogue: 0,0:03:26.40,0:03:33.16,Default,,0000,0000,0000,,[It] turns out that they probably didn’t say that — it’s probably made up — but it makes a good point.
Dialogue: 0,0:03:33.16,0:03:36.46,Default,,0000,0000,0000,,Our first lesson is that in both transit and in cookware,
Dialogue: 0,0:03:36.46,0:03:41.86,Default,,0000,0000,0000,,simply asking people what they want can often miss important opportunities.
Dialogue: 0,0:03:41.86,0:03:46.22,Default,,0000,0000,0000,,The second is that you can find these problems and opportunities — like poor ergonomics —
Dialogue: 0,0:03:46.22,0:03:50.58,Default,,0000,0000,0000,,by going out into the field and discovering what people actually do.
Dialogue: 0,0:03:50.58,0:03:56.45,Default,,0000,0000,0000,,And, third, you can get extra power out of this observation by bringing prototypes along with you.
Dialogue: 0,0:03:56.45,0:03:59.99,Default,,0000,0000,0000,,Fourth, the world is full of people tinkering in their garage,
Dialogue: 0,0:03:59.99,0:04:05.66,Default,,0000,0000,0000,,and everyone wins when the stars align to bring those things into the world.
Dialogue: 0,0:04:05.66,0:04:10.100,Default,,0000,0000,0000,,With measuring cups, like user interfaces, you can think of there as being two steps:
Dialogue: 0,0:04:10.100,0:04:18.60,Default,,0000,0000,0000,,The first is having some action.
Dialogue: 0,0:04:18.60,0:04:22.01,Default,,0000,0000,0000,,And the second is evaluating the outcome.
Dialogue: 0,0:04:22.01,0:04:27.66,Default,,0000,0000,0000,,At each of these steps, you, as a designer, has an opportunity for success or for failure.
Dialogue: 0,0:04:27.66,0:04:33.97,Default,,0000,0000,0000,,In our first step, what you have to cross is the gulf of execution:
Dialogue: 0,0:04:33.97,0:04:37.38,Default,,0000,0000,0000,,How does the user know what to do?
Dialogue: 0,0:04:38.33,0:04:43.42,Default,,0000,0000,0000,,And the gulf that you have to help the user cross is the gulf of evaluation:
Dialogue: 0,0:04:43.42,0:04:46.34,Default,,0000,0000,0000,,How does the user know what happened?
Dialogue: 0,0:04:46.72,0:04:50.85,Default,,0000,0000,0000,,My sketch here is based on a diagram that my colleague Bill Verplank often uses.
Dialogue: 0,0:04:51.56,0:04:59.23,Default,,0000,0000,0000,,As a designer, here are six powerful questions that you can ask to ascertain what challenges may arise:
Dialogue: 0,0:04:59.23,0:05:04.40,Default,,0000,0000,0000,,How usually can someone determine the function of a device, or what actions are possible?
Dialogue: 0,0:05:05.36,0:05:10.54,Default,,0000,0000,0000,,And then, how can I determine the mapping from their goals to their physical movements —
Dialogue: 0,0:05:10.54,0:05:13.68,Default,,0000,0000,0000,,what they actually do with the user interface?
Dialogue: 0,0:05:15.46,0:05:20.28,Default,,0000,0000,0000,,Once they have the plan, how usually can they execute that action?
Dialogue: 0,0:05:21.38,0:05:27.43,Default,,0000,0000,0000,,And, after they’ve executed that action, how usually can they tell what state the system is in
Dialogue: 0,0:05:27.43,0:05:30.41,Default,,0000,0000,0000,,or whether it’s in a desired state?
Dialogue: 0,0:05:30.81,0:05:34.76,Default,,0000,0000,0000,,And, more generally, can they figure out the mapping between the system state
Dialogue: 0,0:05:34.76,0:05:37.42,Default,,0000,0000,0000,,and what they should interpret that to mean?
Dialogue: 0,0:05:38.22,0:05:42.83,Default,,0000,0000,0000,,And, as a designer, here’s several things that you can do to actually make these easier:
Dialogue: 0,0:05:42.85,0:05:48.25,Default,,0000,0000,0000,,The first and simplest is, if there’s functionality that a system can do,
Dialogue: 0,0:05:48.25,0:05:52.27,Default,,0000,0000,0000,,the best way to communicate that to the user is to put that on the screen —
Dialogue: 0,0:05:52.27,0:05:54.100,Default,,0000,0000,0000,,make it visible in one way or another.
Dialogue: 0,0:05:54.100,0:05:59.86,Default,,0000,0000,0000,,And, if it’s in the physical world, give it a handle, or knob, or button.
Dialogue: 0,0:05:59.86,0:06:03.84,Default,,0000,0000,0000,,These cues to action are called “affordances”.
Dialogue: 0,0:06:03.84,0:06:09.06,Default,,0000,0000,0000,,Second, provide users with clear, continuous feedback, so they know exactly what’s happening.
Dialogue: 0,0:06:09.06,0:06:15.60,Default,,0000,0000,0000,,Third, all things equal, be consistent with existing standards, platform conventions, and other idioms.
Dialogue: 0,0:06:15.60,0:06:21.78,Default,,0000,0000,0000,,Fourth, whenever you can, make it possible for people to back up, through Undo or some other mechanism:
Dialogue: 0,0:06:22.62,0:06:25.64,Default,,0000,0000,0000,,Very few things should be permanent and irreversible.
Dialogue: 0,0:06:25.64,0:06:28.90,Default,,0000,0000,0000,,A benefit of having all operations being non-destructive
Dialogue: 0,0:06:28.90,0:06:32.48,Default,,0000,0000,0000,,is that it also enables users to explore and try out things;
Dialogue: 0,0:06:32.48,0:06:34.97,Default,,0000,0000,0000,,and especially in creative applications,
Dialogue: 0,0:06:34.97,0:06:39.85,Default,,0000,0000,0000,,you see that people will try down branches and use Undo to come back.
Dialogue: 0,0:06:40.28,0:06:47.14,Default,,0000,0000,0000,,Fifth, provide a systematic way for people to discover all of the functionality available in an application.
Dialogue: 0,0:06:47.14,0:06:50.13,Default,,0000,0000,0000,,If you watched somebody use a new website, for example,
Dialogue: 0,0:06:50.13,0:06:53.96,Default,,0000,0000,0000,,one thing that you might see them do when they’re trying to figure out how to navigate it,
Dialogue: 0,0:06:53.96,0:07:00.02,Default,,0000,0000,0000,,is [to] roll over all the menu bars, to see what every option that’s out there is.
Dialogue: 0,0:07:00.50,0:07:04.69,Default,,0000,0000,0000,,And, finally, reliable software {\i1}is{\i0} a usability issue:
Dialogue: 0,0:07:04.69,0:07:09.97,Default,,0000,0000,0000,,The thing that’s supposed to happen should [happen]; and random stuff that isn’t, shouldn’t.
Dialogue: 0,0:07:09.97,0:07:13.93,Default,,0000,0000,0000,,I know that reliability is easier said than done, but it’s still really important;
Dialogue: 0,0:07:13.93,0:07:18.67,Default,,0000,0000,0000,,and a lot of the interfaces that people really like have this property of reliability.
Dialogue: 0,0:07:18.67,0:07:23.58,Default,,0000,0000,0000,,So, now that we have these new conceptual tools of a gulf of execution and evaluation —
Dialogue: 0,0:07:23.58,0:07:29.56,Default,,0000,0000,0000,,of knowing what you can do and whether what you’ve wanted is what happened —
Dialogue: 0,0:07:29.56,0:07:33.98,Default,,0000,0000,0000,,let’s take a look at a video that Bill Moggridge and colleagues at IDEO put together
Dialogue: 0,0:07:33.98,0:07:38.74,Default,,0000,0000,0000,,about someone trying to buy a soda from a vending machine in Japan
Dialogue: 0,0:07:38.74,0:07:41.62,Default,,0000,0000,0000,,using their mobile phone.
Dialogue: 0,0:07:41.62,0:07:45.67,Default,,0000,0000,0000,,While you’re watching this video, think about what’s causing the breakdowns,
Dialogue: 0,0:07:45.67,0:07:53.40,Default,,0000,0000,0000,,and how you might fix them by using the bullet points that we’ve outlined in this lecture today.
Dialogue: 0,0:10:26.58,0:10:29.12,Default,,0000,0000,0000,,We started out today looking at physical products,
Dialogue: 0,0:10:29.12,0:10:32.88,Default,,0000,0000,0000,,and we moved on to explore smart products and mobile phones.
Dialogue: 0,0:10:32.88,0:10:38.83,Default,,0000,0000,0000,,Now let’s think about what direct manipulation and the gulfs of execution and evalution mean
Dialogue: 0,0:10:38.83,0:10:41.24,Default,,0000,0000,0000,,for building software.
Dialogue: 0,0:10:41.24,0:10:46.03,Default,,0000,0000,0000,,What’s better? A command line or a graphical user interface?
Dialogue: 0,0:10:46.03,0:10:49.44,Default,,0000,0000,0000,,Well, I think the answer is going to have to be “it depends.”
Dialogue: 0,0:10:49.44,0:10:53.57,Default,,0000,0000,0000,,Nearly every design is good for something and bad for something else.
Dialogue: 0,0:10:53.57,0:10:59.41,Default,,0000,0000,0000,,But let’s try to figure out what makes them different: think about moving a file between two folders.
Dialogue: 0,0:10:59.41,0:11:04.74,Default,,0000,0000,0000,,On a graphical user interface, you simply pick it up in one location, and drop it in another:
Dialogue: 0,0:11:04.74,0:11:09.77,Default,,0000,0000,0000,,You have continuous feedback about what’s happening.
Dialogue: 0,0:11:09.77,0:11:13.84,Default,,0000,0000,0000,,All of the objects that are of interest to you are available onscreen,
Dialogue: 0,0:11:13.84,0:11:18.52,Default,,0000,0000,0000,,and you can simply point at what you want — “input on output”.
Dialogue: 0,0:11:18.52,0:11:24.30,Default,,0000,0000,0000,,With a command line, you have to know, a priori, what the name of the command that is that you’d like to use.
Dialogue: 0,0:11:24.30,0:11:29.11,Default,,0000,0000,0000,,You also have to remember the syntax for using that move command
Dialogue: 0,0:11:29.11,0:11:32.38,Default,,0000,0000,0000,,there’s minimal feedback about whether the operators that you’re dealing with —
Dialogue: 0,0:11:32.38,0:11:36.46,Default,,0000,0000,0000,,like files or folders — are actually available,
Dialogue: 0,0:11:36.46,0:11:41.22,Default,,0000,0000,0000,,and there’s not much in confirmation that you’ve moved it ultimately to the right place —
Dialogue: 0,0:11:41.22,0:11:44.87,Default,,0000,0000,0000,,it can be easy to make errors.
Dialogue: 0,0:11:44.87,0:11:49.10,Default,,0000,0000,0000,,What we see with the graphical interface is the power of direct manipulation —
Dialogue: 0,0:11:49.10,0:11:54.16,Default,,0000,0000,0000,,immediate feedback on all actions, continuous representations of the objects,
Dialogue: 0,0:11:54.16,0:11:58.21,Default,,0000,0000,0000,,and they leverage metaphors that we have from the physical world.
Dialogue: 0,0:11:58.21,0:12:01.36,Default,,0000,0000,0000,,These metaphors are especially important when you’re learning a new interface,
Dialogue: 0,0:12:01.36,0:12:04.21,Default,,0000,0000,0000,,and so when the graphical interface was first released,
Dialogue: 0,0:12:04.21,0:12:09.69,Default,,0000,0000,0000,,being able to rely on what people knew about desks, folders, and files was really helpful;
Dialogue: 0,0:12:09.69,0:12:14.72,Default,,0000,0000,0000,,those become less valuable once you’ve become accustomed to the computer world.
Dialogue: 0,0:12:14.72,0:12:17.90,Default,,0000,0000,0000,,So, give some thought to which of these principles hold
Dialogue: 0,0:12:17.90,0:12:21.78,Default,,0000,0000,0000,,for both the command-line interface and the graphical interface.
Dialogue: 0,0:12:22.95,0:12:23.89,Default,,0000,0000,0000,,From my perspective,
Dialogue: 0,0:12:23.89,0:12:30.86,Default,,0000,0000,0000,,the graphical interface does a much better job in terms of visibility, feedback, and consistency.
Dialogue: 0,0:12:34.29,0:12:37.12,Default,,0000,0000,0000,,In either interface style, Undo is possible,
Dialogue: 0,0:12:37.12,0:12:42.30,Default,,0000,0000,0000,,although the GUI generally does a better job of exposing when Undo is available
Dialogue: 0,0:12:42.30,0:12:46.28,Default,,0000,0000,0000,,and what undoing will actually do.
Dialogue: 0,0:12:48.50,0:12:53.20,Default,,0000,0000,0000,,One place that a graphical interface really shines is in terms of discoverability —
Dialogue: 0,0:12:53.20,0:12:58.87,Default,,0000,0000,0000,,you can leaf through every single menu in a system, and see all of the operations that are there;
Dialogue: 0,0:12:58.87,0:13:00.54,Default,,0000,0000,0000,,with a command-line interface,
Dialogue: 0,0:13:00.54,0:13:07.28,Default,,0000,0000,0000,,there’s really no way to know what’s the full set of operations that you could possible type into a terminal.
Dialogue: 0,0:13:07.28,0:13:11.76,Default,,0000,0000,0000,,There’s no mater list.
Dialogue: 0,0:13:11.76,0:13:17.38,Default,,0000,0000,0000,,In terms of reliability, either interface style can be made to be reliable.
Dialogue: 0,0:13:19.68,0:13:22.50,Default,,0000,0000,0000,,“But how can this be?” some of you may be saying,
Dialogue: 0,0:13:22.50,0:13:27.04,Default,,0000,0000,0000,,“The command-line interface can be so much better sometimes!”
Dialogue: 0,0:13:27.04,0:13:29.97,Default,,0000,0000,0000,,And it is!
Dialogue: 0,0:13:29.97,0:13:31.20,Default,,0000,0000,0000,,When is that?
Dialogue: 0,0:13:31.20,0:13:33.48,Default,,0000,0000,0000,,The command-line interface works better
Dialogue: 0,0:13:33.48,0:13:39.74,Default,,0000,0000,0000,,when the indirection that it offers is a benefit rather than a drawback.
Dialogue: 0,0:13:39.74,0:13:43.28,Default,,0000,0000,0000,,And in fact that indirection that it offers is a kind of abstraction,
Dialogue: 0,0:13:43.28,0:13:45.70,Default,,0000,0000,0000,,and that’s what gives programming its power,
Dialogue: 0,0:13:45.70,0:13:51.18,Default,,0000,0000,0000,,and so the command-line interface, like programming — because in some way it kind of is programming —
Dialogue: 0,0:13:51.18,0:13:59.55,Default,,0000,0000,0000,,gets its power when you can express stuff more abstractly and thereby do work more efficiently.
Dialogue: 0,0:13:59.55,0:14:06.55,Default,,0000,0000,0000,,So, for example, moving all of the files that match a certain set of criteria from one place to another,
Dialogue: 0,0:14:06.55,0:14:11.31,Default,,0000,0000,0000,,that can sometimes be more efficiently accomplished with a command line.
Dialogue: 0,0:14:11.31,0:14:16.35,Default,,0000,0000,0000,,And even that wonderful discoverability of the graphical user interface has a dark side:
Dialogue: 0,0:14:16.86,0:14:19.77,Default,,0000,0000,0000,,This is a picture from my colleague Takeo Igarashi.
Dialogue: 0,0:14:19.77,0:14:25.88,Default,,0000,0000,0000,,Takeo made this picture by turning on all of the menu bars in a certain version of Microsoft [PowerPoint].
Dialogue: 0,0:14:25.88,0:14:32.13,Default,,0000,0000,0000,,And you can see that, on his laptop screen, all of those menu bars crowded things out so much
Dialogue: 0,0:14:32.13,0:14:35.94,Default,,0000,0000,0000,,that there was almost no screen left over for the slides.
Dialogue: 0,0:14:35.94,0:14:41.32,Default,,0000,0000,0000,,So, is this interface discoverable? Absolutely! All of the functionality is right there.
Dialogue: 0,0:14:41.32,0:14:45.86,Default,,0000,0000,0000,,But you pay a cost in terms of screen real estate.
Dialogue: 0,0:14:45.86,0:14:50.09,Default,,0000,0000,0000,,In this introductory course, we won’t have a chance to talk much about gestural interfaces.
Dialogue: 0,0:14:50.09,0:14:54.06,Default,,0000,0000,0000,,But, given their recent popularity, and tablet interfaces, game controllers,
Dialogue: 0,0:14:54.06,0:15:00.42,Default,,0000,0000,0000,,and movies like « the Minority Report », I want to conclude today’s lecture with an eye to the future:
Dialogue: 0,0:15:00.42,0:15:04.46,Default,,0000,0000,0000,,Gestural interfaces offer a wonderful solution to menu creep,
Dialogue: 0,0:15:04.46,0:15:08.44,Default,,0000,0000,0000,,in that they don’t take up any permanent screen real estate.
Dialogue: 0,0:15:08.44,0:15:13.64,Default,,0000,0000,0000,,The downside, of course, is that they are non–self-disclosing —
Dialogue: 0,0:15:13.64,0:15:17.87,Default,,0000,0000,0000,,you don’t know what functionality might be available.
Dialogue: 0,0:15:17.87,0:15:24.90,Default,,0000,0000,0000,,And, at their best, gestural interfaces can be even more direct than their graphical user interface counterpart.
Dialogue: 0,0:15:24.90,0:15:31.16,Default,,0000,0000,0000,,In recent years, I’ve watched in amazement at people of all ages and from all backgrounds
Dialogue: 0,0:15:31.16,0:15:35.68,Default,,0000,0000,0000,,have figured out how to use tablet computers really effectively.
Dialogue: 0,0:15:35.68,0:15:39.09,Default,,0000,0000,0000,,And the directness, I think, is one big reason for that.
Dialogue: 0,0:15:39.09,0:15:42.15,Default,,0000,0000,0000,,Learning to use a mouse is actually kind of a big deal:
Dialogue: 0,0:15:42.15,0:15:44.44,Default,,0000,0000,0000,,Once you’ve got the hang of it you forget that,
Dialogue: 0,0:15:44.44,0:15:46.90,Default,,0000,0000,0000,,but there {\i1}is{\i0} this indirectness that you’ll have to learn
Dialogue: 0,0:15:46.90,0:15:51.00,Default,,0000,0000,0000,,that what you’re doing over here matters over here.
Dialogue: 0,0:15:51.00,0:15:56.25,Default,,0000,0000,0000,,With a tablet, the thing that you touch is the thing that you’re interacting with.
Dialogue: 0,0:15:56.25,0:16:02.63,Default,,0000,0000,0000,,And the best gestures in these interfaces, like pinching to zoom, just feels so natural —
Dialogue: 0,0:16:02.63,0:16:09.42,Default,,0000,0000,0000,,the metaphor is very clear, the feedback is immediate, the outcome is predictable.
Dialogue: 0,0:16:09.42,0:16:14.15,Default,,0000,0000,0000,,In other cases, when the mapping is more arbitrary or harder to guess,
Dialogue: 0,0:16:14.15,0:16:16.67,Default,,0000,0000,0000,,I think these interfaces are less effective.
Dialogue: 0,0:16:16.67,0:16:23.90,Default,,0000,0000,0000,,For example, if I swipe with four fingers, that will bring up a menu bar on an iPad.
Dialogue: 0,0:16:23.90,0:16:27.55,Default,,0000,0000,0000,,How on earth would I ever figure that out?
Dialogue: 0,0:16:27.55,0:16:32.54,Default,,0000,0000,0000,,So, in gestural interfaces, like in all others, things work best when the feedback is clear,
Dialogue: 0,0:16:32.54,0:16:37.74,Default,,0000,0000,0000,,and the interface provides cues through metaphors or visual signals
Dialogue: 0,0:16:37.74,0:16:41.78,Default,,0000,0000,0000,,that help you know what you can do within the user interface.
Dialogue: 0,0:16:41.78,0:16:45.90,Default,,0000,0000,0000,,To learn more about direct manipulation interfaces and the psychology of design,
Dialogue: 0,0:16:45.90,0:16:50.29,Default,,0000,0000,0000,,I strongly recommend Don Norman’s book « The Design of Everyday Things ».
Dialogue: 0,0:16:50.29,0:16:53.17,Default,,0000,0000,0000,,We’ll see you next time.