What Can We Learn From The GUI?

There are, naturally, many advantages to graphical user interfaces (GUIs). They are typically oriented around presenting options, rather than requesting open-ended instructions, which makes them less potent than command-line interfaces, but also easier to learn to use. However, I believe that there are other advantages to current GUI systems which may be applicable to command-line interfaces as well.

• Flexibility of data display
  
  GUI applications typically provide a rich and flexible data display, allowing the user to scroll freely through the contents and perform standard operations (such as use of the clipboard) the manipulate the data.
• Assistance during complex input
  
  In GUI applications, it is typically the case that if you need to perform a complex series of decisions, you receive a certain amount of assistance with this. For instance, it would typically be the case that a GUI program used to control encoding of video files would present the user with a window containing checkboxes and drop-down lists to control things like selection of encoding format, bitrates, and various options. In CLI applications the process is often much more difficult: such encoding options would likely need to be specified all at once on the command line. The information on what the switches are and what they do is generally provided through documentation, and so the process of specifying a long series of options may require repeated reference to the documentation for the options in question. And then, if the command as specified is missing an option, one of two things could happen. The first is that the command will simply be rejected. The second is that the command could run and then (to provide a better UI) prompt the user for the missing value. In the second case, however, the option specified in response to the prompt would not be a part of the command as recorded in the command history of the shell.