What is human-computer interaction (HCI), and what disciplines contribute to it?
HCI is the process "through which people operate and engage with computer systems." HCI essentially examines how interface design and user experience affect the way by which humans interact with technology. HCI is a multidisciplinary field, which combines computing, behavioral sciences (such as psychology and sociology), design, and more.
What is the difference between a system being useful and being usable? Can you give an example of a system that is usable but not useful for a particular person or task?
A useful system is one which can be used by humans to carry out a particular task. Or, in essence, it is a "system that does what it should." A usable system is one that is easy to use, not one that solves a particular problem.
An example of this could be a sink, for instance, and a washing machine. The sink is usable, but not particularly useful to do the laundry.
Find an everyday interface that is confusing to use. What is the person trying to do, and which design decision causes difficulty? Suggest one improvement.
A drier. The interface is very confusing due to the lack of words and clear images. The creator is trying to hint at what each button does, but the symbols used are very confusing. (I just did my laundry).
What is a prototype, and how can testing one with users help a designer? What is one thing that asking "Do you like it?" would not tell you?
A prototype is an early model of a specific application or digital/physical product. It is used to test whether the product has any bugs or not, or if the design is working the way it should.
The question "do you like it" would not give you actual feedback as to the usability or the convenience of the product, or whether the user would actually use the product instead of alternatives.
Find one example of interaction beyond a keyboard and mouse, such as voice input or a tangible interface. Who might benefit, and how would you test whether it helps them?
We could use 'visual sounds,' which is basically a feature that tells a person what sounds the computer is currently making/outputting. This would help deaf people along with subtitles, as subtitles alone are (usually), not enough. For instance, when they are playing a game, a 'gunshot' from the right could show on the screen. A way to test whether it would help them or not is by the use of a prototype. Prototype testing could lead to the conclusion of whether deaf people were able to report less confusion and find 'sound sources' more quickly.