Interface Design Primer
Computers are pretty dumb devices. They can only count on two fingers, but they can do so incredibly quickly.
When programmers communicate with their computers, they use languages that they can understand as well as the computer. These languages are not simple binary 0 and 1s, but they aren't plain English either, they are something in between, a bit like speaking in abbreviations. As long as the programmer and the computer know what the abbreviations mean, everything works fine.
A level up from programming languages is command-line languages like UNIX and MSDOS. Here, you will see some English words like PRINT or GET but a lot of it is still mumbo jumbo that is difficult to remember and unless you are a fast and accurate typist, liable to frequent mistakes and frustration.
Here is an example from the 'Basics' section of 'UNIX for DUMMIES'.
gs –sDEVICE=deskjet –dNOPAUSE –sOutputFile=floogle.lj floogle.ps quit.ps
Most computer users just want to enter numbers or words and to be able to manipulate, save and retrieve their data quickly and easily. The computer should do all the hard work – after all, that's what it's paid for!
When you go into a restaurant and the waiter comes to your table, you don't have to describe the kind of food you want to eat in great detail or spell out the recipe step by step. You choose from a menu. The menu won't have every type of food and every possible combination. It is a 'set menu' to simplify the process of ordering and cooking food for the restaurateur and it is also makes it easier for you, the customer, if there aren't too many choices.
Using a software program or Web page is primarily about making choices too. Before pointing devices like the mouse came along, the interface to most programs was a series of menus and you selected menu items by pressing buttons on the keyboard – "Press the P key to Print".
A mouse makes choosing items from a menu even easier. When I say 'menu', don't take that too literally, I don't mean just pop-down menus but any situation where you are presented with choices - a series of words, icons or pictures that are 'interactive' and not passive. A line of text on a page is passive, it is just information. Interactive text, like a Web page hyperlink, does something when you click on it.
The whole point of a Graphical User Interface is that it allows the user to interact with a computer without having to enter cryptic commands from a keyboard. It is just a matter of point and click, or click and drag. If there is any easier way to control a computer, short of a direct brain implant, I haven't seen it.