Efficient user interfaces

Question

Speed and learnability do not directly fight each other, but it seems easy enough to design such a GUI that lacks either (or both) of them. GUI designers seem to prefer \'easy t

Answer 1

Rant (or, Stuff I think you should keep in mind):

Speed and learnability do directly fight each other. A menu item tells you what it does so that you don't have to remember. But it's much slower than a keyboard shortcut that you have to memorize to benefit from. The general technique for resolving this conflict seems to be allowing more than one way of doing things. While one way of doing something usually cannot be both fast and easy to learn, you can often provide two ways to accomplish the same task: one that's fast, and one that's obvious.

There are different kinds of people. The learning gap is a result of interest, motivation, intellectual capacity, etc. There is a class of person that will never bother to even learn which menu provides the action they want, and they'll scrub the menubar every time. There is also a (minority) class of person that thinks vim (or emacs) is the best thing since sliced bread. Most people probably fall somewhere in between these extremes.

My answer to the actual question:

I think you are asking how to strive for a fast UI. Your question wasn't particularly clear (to me).

• First of all, be consistent. This helps both speed and learnability. Self consistency is the most important, but consistency with your environment may also be important.

• For real speed, require as little attention and motion as possible. Keyboard shortcuts are fast because experienced users know where they are (they don't have to look), and their hands are already on the keyboard. Especially avoid forcing the user to change their position in front of the computer (e.g., moving one hand between the mouse and keyboard).

• The keyboard is almost always faster than the mouse.

• Customization (especially the ability to write custom scripts) will let power users make the interface work the way that is fastest for their specific habits.

• Make it possible to get by without the most powerful features. All you need to know in order to survive in vim is "i, ESC, :wq, :q!". With that, you can use vi about the same way a lot of people use notepad. but once you start learning "h,j,k,l,w,b,e,d,c" (and so on) you get much more efficient. So there is a steep learning curve, but you can get by until you surmount it.

• Keep in mind that if you focus on interface efficiency, you will probably limit your user base. Vim is popular among programmers, but lots of programmers use other tools, and it's virtually unknown among non-programmers. Most people want easy, not fast. Some want a balance. A very few just want fast.

Answer 2

While I've been writing my own UI I've understood couple of things myself.

I imitated vim, but at the same time realized why it's so fast to use for text editing. It is because it acknowledges a thing: People prefer doing one thing at a time (inserting text, navigating around, selecting text), but they may switch the task often.

This means that you can pack different activities into different modes if you keep the mode switching schemes simple. It gives space for more commands. The user also gets better chances at learning the full interface because they are sensibly grouped already.

Vim is practically stuffed full of commands, every letter in the keyboard does something in vim, depending on the mode. Still I can remember most of them. And it's all because of modes.

I know bunch of projects that sneer at mode-dependent behavior. Main argument is the uncertainty of which mode you are in. In vim I'm never uncertain about the mode where I am in. Therefore I say the interface design is a failure if a trained user fails to recognize in which mode the interface is operating at the moment.

Answer 3

The main thing to be careful of is putting UI elements where they are most commonly located for other applications in that environment. For example, if you're going to make use of a menu system, people are accustomed to it being along top of the window by default for a desktop application. If you're in a web browser a menu system on a webpage seems out of place because it's not a consistent feature. If you're going to have an options/preferences configuration window, people are used to finding it under the Tools menu option, occasionally under the Edit menu. The main thing with keeping a UI "easy to learn" is that your UI elements shouldn't break the mold too much of how they're used in other applications.

If you haven't had the opportunity to see Mark Miller's presentation on The Science of Great User Experience, I'd recommend you watch the DNR TV episodes Part 1 and Part 2.

Answer 4

Beyond avoiding an angry fruit salad, just try to make it as intuitive as possible. Typically, programs with a very frustrating UI share one common problem, the developers didn't define a clear scope of what the program would actually do prior to marrying a UI design.

Its not so much a question of 'easy' , some people jump right into the UI and begin writing stuff to back the interface, rather than writing the core of a planned program and then planning an interface to use it.

This goes for web apps, desktop apps .. or even command line programs. A good design means writing the user interface after (and only after) you are sure that 'scope creep' is no longer a possibility.

Sure, you need some interface to test your program, but be prepared to trash it and do something better prior to releasing the program. Otherwise, there's a good chance that the UI is only going to make sense to you.

Answer 5

We have a product in our lineup that has won numerous awards based largely on its ability to provide more power with an easier interface than any of our competitors. I designed the interface a few years after holding a position in one of Bell Labs' human interface research groups so I had a pretty clear idea of what constituted "success" when I approached it. I have four pieces of design advice for creating easy but powerful interfaces.

First, select a metaphor that makes sense in their environment and do your best to stick to it. This doesn't have to be a physical metaphor although that can help if working with people who are not tech savvy. This was popular in the early days of Windows but its value remains. We used a "folder and page" metaphor that permitted us to organize a wide range of tasks while not crimping power users' style.

Second, offer a consistent layout relationship between data display and tasks. In our interface, each "page" displays a set of action buttons in the exact same position and, wherever possible, uses the same actual buttons. Thus, once one page is learned, the user has a head start on learning the rest. One of these buttons, always placed in a distinctive position, is a "Help" button...which brings me to point #3. The more general rule is: find ways of leveraging learning in one area to assist in learning others.

Third, offer context-sensitive help and make sure that it addresses the user's primary question (which is usually "what do I do now"?) How often have you seen technical help that simply shows you the Inheritance tree, constructor syntax and an alphabetical list of methods? That isn't help, it is abuse. We focused all of our help on walking people through sample tasks. In particularly tough areas, we also offered multimedia tutorials.

Fourth, offer users the ability to customize the interface. Our users often had no use for specific "pages" (analysis types) in their work. Thus, we made it very simple to turn them off so that the user would see an interface that was no more complicated than it had to be. Our app was usually installed by a power user and then used by multiple staff members so this was more of a win for us because we could usually count on the power user to understand what to shut off. However, I think it is good advice in general.

Good luck!

Answer 6

Autocad has a console mode. As you do things using the mouse and toolbars, the text-equivalent of those commands is written to the console. You can type commands directly in there. This provides a great way to learn the power-user names for commands (they are very short, like unix commands) which aids greatly the process of moving from beginner to productive power-user. Generally speaking, one primary focus has to be in minimising movement between the mouse and keyboard, so put lots of functionality into the mouse, or into the keyboard, because when you have to move your hands like that, there is a real delay in trying to find the right place to put them.