But you can prevent identity theft from occurring by installing a firewall. A firewall is software that checks all data entering and exiting a computer and it then blocks that which doesn't meet specified security criteria (user-defined rules).1 5. Don't click on website links in spam messages. In an effort to obtain personal information, some spammers will send email that asks you to click on a link. 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! As reported in countless news reports, computer viruses are rampant and they're extremely worrisome. This article will describe what viruses are and then point you in the direction of some rather unique protection and prevention. In short, a computer virus is a software program designed to destroy or steal data. Identifying Compressed Files Most files are compressed in .zip format (if you're using Windows) or .sit format (if you're using a Mac). The two most popular software programs used to compress and decompress files are Winzip and StuffIt respectively. There are other programs that do the same thing and there are even programs that can compress and decompress files for both the Windows and the Mac system. Batch files are plain text files, and you can build one for your own personal use with Windows' Notepad. You could make a batch file that loads up your favorite websites at once for example, or you could make a batch file that fills your desktop with the most important applications for the day. To do so only requires a little knowledge about the locations of these applications. The fan is located on the computer's CPU unit and when that thing gets clogged with dirt and dust, it can run down a computer faster than you can say, "Something's wrong with my computer and I don't know what it is!" In short, the fan is responsible for keeping a computer's motor cool and this motor is what keeps the computer's hard drive and peripherals functioning the way you need them to, which translates to "fast.