The convenience of having information at our immediate access is phenomenal - so much so that thousands of programmers have jumped on the opportunity to build unique applications specific to these small machines. As a result, you can find tons of games, databases, GPA systems, weather reporting programs, and even small encyclopedias on these things - each accessible not at the click of a mouse - but at a few presses of a free thumb. Windows Media Player will open and run these files, however they don't sound like normal .wav or .mp3 files (described later). .Mid files are designed to product synthetic sounds using a computer's sound card. .mp3 - This extension indicates a sound file that authentically reproduces voice and/or music. Innocent people become pawns for the evil plans of others who've convinced themselves they're doing the "right" thing. To protect a computer from getting a virus, or clean a virus from a computer system once infected requires the use of an antivirus utility. But may be something else we can do. Deletion programs will analyze a computer's operating system and installed programs to determine which files are crucial to computer function versus which files are safe to delete. You already have such a program on your computer and it's Windows' Add/Remove Programs (available from the Control Panel). Gas stations are self-serviced through a menu-clad touch screen kiosk. 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. Other people have found much more creative and effective ways to use batch files, but the important thing is that you know they're a resource you can use to save a few seconds or minutes in performing important tasks. We've come a long way from MS-DOS, but it's still a valuable source of automation that anyone can use with no programming knowledge at all.