It's quite easy to cause more damage from cleaning so if you're not comfortable with cleaning your PC yourself, take it to a shop for servicing. Otherwise, you can unplug and disassemble the computer to do it yourself. You'll need a can of compressed air and an anti-static rag to remove stubborn clumps of dust.

But when they're typed into a programming language and compiled to create a an executable file (a file ending with the .exe extension), they turn into a software application. As we mentioned earlier, you can use a programming language to control your computer. By using simple commands, you can program your computer to perform mathematical tasks, fill out web forms, compose an email message and send it off, or any number of other things.

Only this time, you'll set up a LAN (Local Area Network) connection. Windows should walk you through setting up a LAN after starting the computer and once complete, you can begin to connect one of your machines to the network. You can do this through Internet Explorer by typing in the address and password required to access the router (the address and password required to access the router will be in the router manual).

Fans of open source programs are adamant about reliable software and highly criticize commercialized versions for being buggy and error-prone. Avid fans even proclaim commercialism is the cause of shoddy software. Another benefit that open source brings to light is the speed at which its products are developed, enhanced, supported and distributed.

Today's "older" computers are perfectly capable of accommodating the needs of young PC users, and they're excellent machines for playing educational CDs, small multimedia files, or games downloaded from the Internet. And don't forget the most important role they play in a child's homework-clad life: A simple encyclopedia CD on a used computer makes excellent research tool (not to mention a rather fancy calculator!

Most cash registers are Windows XP or Vista machines that send purchase details back to headquarters via the Internet (or a small Intranet). Having your weight, blood pressure, and heart rate measured and recorded is now a digitized process. Even ordering a pizza is now a simple matter of dialing from a wireless cell phone and making a few selections from series of pre-programmed menus!