The Design of Everyday Things

1) Donald A. Norman hit on many key points throughout this chapter. One key point is the importance of visibility; the correct parts need to be visible. Norman gives the example of scissors, it’s easy to see that one would insert their fingers into the holes, and even if they do not insert the correct fingers, the scissors are still usable and efficient. Another key point is having a good conceptual model. Reverting back to the scissors example, they also have a good conceptual model. A conceptual model is the relationship between the operating controls and the function. It’s easy for anyone to understand that when you open your fingers the scissors will open and vice versa.

2) A product that I have had a history of not understanding and have had trouble using are copying machines. Some copy machines have touch screen interfaces and some have the standard button interfaces. The copy machine should be simple to use, you insert a piece of paper, press a button and it makes a copy. However the number of features far exceeds the number of buttons they have choose to include on the interface. Many of the buttons have multiple features assigned to them, such as the start button is also teamed up with the menu button. I find that my copies always come out incorrect and I waste resources such as ink, paper and not to mention my time because of it. The usability, actually the un-usability of copy machines definitely arises from the principles that Norman discussed in the chapter. The problem with the machine is that the buttons you need are not clearly visible. To go along with these issues, there is no correlation between the buttons you press and what the machine will do. This would be referred to as a poor conceptual model.

3) The designers of the iPod addressed the issues that Norman discussed in a couple of different ways. Norman discusses at great lengths that visibility of important buttons. When the iPod was first being designed, they were devoted to keeping it simple. Steve Jobs did not want to include even a power switch because he wanted the least amount of buttons possible, while still being usable. On the note of conceptual models, the original iPod used the thumb wheel. When you slid your thumb to the right you scrolled down through your songs, and when you slid your finger to the left you scrolled upwards. The movement of your thumb directly relates to the direction you scroll through the songs, which promotes a good conceptual model. The iPod design team also addressed the principle Norman’s discussed of constraint. Constraints provide a visual map that limit the way you can use a certain thing. So for the iPod’s thumb wheel, people would understand that it would be operated using only a single finger as opposed to a full hand or all the fingers. The designers have used the discussed psychological principles to cut down on the learning curve but to still maximize the amount of tasks you can perform.