As a software user, this means you can contribute to an open source project as well, and help to develop it into a product that reflects your direct preferences. You aren't "stuck" using open source software the way you would be stuck using an expensive word processor or database. You have the same access to open source software as its programmers have and in essence, you are your own customer! Why viruses exist remains a mystery, however we had privy access to the mind behind a virus programmer who explained his motivation behind his destructive inclinations. Apparently, this person had a deep grudge against a popular online service which shall remain unnamed. In this hacker's mind, the online service failed to do a quality job in protecting children from online smut and as retaliation, he created and distributed a virus to as many file libraries of this service as he could. The floppy not only stored the program (word processor, spreadsheet, etc.), it also stored the drivers that the program needed to communicate with the computer's hardware. As you can imagine, the cumbersome process of switching from floppy to floppy prompted the birth of the operating system. An operating system is a software program that controls how the computer's hardware (and installed software) works. A file could be a plain text file, an image, a sound, a video, or program. But without seeing the extension, you wouldn't know it unless you double-clicked on it. The following list defines some of the most common extensions that you'll find on your computer. .au - This extension indicates a sound file. Introduction to Programming Controlling Your Computer with a Programming Language In a previous article, we introduced automating some tasks with MS-DOS batch files. In this article, we're going to introduce programming and describe how it can be used to control the way your computer works. Normally, computer novices aren't interested in controlling the computer. In other words, we can discover whether the software performs the way we want them to and should anyone try to do the same with commercial software, they'll be in for a big disappointment. Commercial software policy doesn't even allow for returns, let alone "borrowing" them to try them. The last advantage that shareware has over commercial software (but certainly not the least) is its applicability.