So you’ve logged into a Linux® system… or a Windows system.. or a Mac.

You’re presented with a screen with icons on it that represent programs. You can run each of these programs by double clicking on them with your mouse, named Fred. Why Fred? Well, it seems like a mousy name.

So you’ve double clicked on a program and it started up. It isn’t quite running how you want, which isn’t Fred’s fault, but you have to use Fred to find the properties in the program to change them around so that it is working how you want it to.

Which means quite a bit of time with Fred. You can usually preset your program to run the way you want it to, but what about the times when you want it to run slightly different? Well, back to Fred. Fred is a friendly mouse, but all the time with Fred means less time with your keyboard.

So the solution to less time with Fred and more time with the keyboard is the command line. The command line is actually a program in Linux® called the ‘terminal’. Or the ‘xterm’ or the ‘gnome terminal’ or… it all depends on how your Linux is set up.

In the old days, it was the only way to communicate with the computer. Now we have Fred and icons to click, but occasionally, the command line is useful. It has many names, you can read more about the history at Wikipedia.

Back to the command line. With it we can start a program and give it precisely the options we want so that it’ll run the way we want it to. We can start a game, a word processor, a web browser, a pdf viewer… Anything that can be opened with the click of the mouse can be opened by typing a command in the command line, which explains the name.

So in summary, icons are like concrete, command line is like balsa wood.