Almost all software accompanies a list of system requirements which dictates what a computer needs to have in order for the software to work properly. To minimize errors of this sort, always verify that your computer has the required components. A project management program that you're interested in may require a specific operating system, like Windows XP for example. exe - This extension indicates a program or an application like Microsoft Word, Internet Explorer, or Outlook Express. Use extreme caution when downloading .exe files from the Internet since malicious programmers like to hide viruses in these types of files. .gif - This extension indicates another image file and it stands for "Graphics Interchange Format. Decide what you'll use the computer for. If you want to use your computer for cruising the web, sending email, or performing simple word-processing or spreadsheet tasks, a computer with the basic components that we just described should suffice. If you want to use a computer to help with a career in multimedia however, you're going to need to accessorize your system with a scanner, printer, digital camera, tablet, or digicam for example. Waiting too long to accessorize can cause more problems than necessary because while you wait, manufacturers continuously develop new technologies - technologies that your computer won't be able to accommodate in the future. Once you're ready to accessorize, the new products on the market are too advanced for your computer and they just won't work. The data that a program receives is called input and data that the program generates is called output. Other times, the data is unknown. If the program were working with a simple algebra equation like, "x + 5 = y," the variables "x" and "y" would be unknown pieces of data. 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.