In an effort to be "user-friendly," Windows (as well as other operating systems) hide the most important part of a file name from new computer users: the extension. Let's assume that the reason behind hiding extensions is a "user-friendly" one because there just isn't another known reason for hiding them. No harm could ever come from seeing an extension, but plenty could be learned from it. Fortunately this article will guide you through some of the most common extensions used.
File extensions must be turned on before you can see them, so, from Windows Explorer, click on the "Tools" menu, and select "File Options." Click the "View" tab and uncheck the box next to "Hide file extensions for known file types" and click "OK". Notice the files in Windows Explorer now show a dot and group of three letters after the file name. That dot and three letter grouping is known as an "extension," and the extension explains what type of file you are viewing.
Files range from plain text file to image, sound, video and program but without seeing the extension, it is difficult to tell the file type unless it is double-clicked. The following list defines the most commonly found extensions on a computer.
.au - This indicates a sound file. Most sound players will load up and play this kind of file.
.art - This indicates an image file that has been compressed using AOL (America Online) technology. This extension is also compatible with Internet Explorer if AOL has not been installed to your system.
.avi - This indicates a video file playable by most multimedia viewers including Microsoft's Media Player.
.bmp - This indicates another image file that may have originated from Windows Paint program.
.dll - This indicates a Dynamic Link Library which may contain additional programming code for software. Different programs often share Dynamic Link Libraries and many can be found in the Windows/System directory (don't ever delete them)!
.exe - This indicates a program or an application like Internet Explorer, Outlook Express, or some other type of executable desktop program. Use extreme caution when downloading .exe files from the Internet because malicious programmers often hide viruses in this type of file.
.gif - This indicates another image file and means "Graphics Interchange Format." .Gif files are often smaller than .bmp files (described earlier) and are commonly found on Internet web pages.
.jpg - This indicates yet another image file and means "Joint Photographers Experts Group." Like the .gif file, Internet web pages use .jpg because it is much smaller than either the .gif image or the .bmp image.
.mid - This indicates a sound file created with a Musical Instrument Digital Interface. Windows Media Player will open and run these files, however they don't sound like a normal .wav or .mp3 file (described later) because they are designed to produce synthetic sounds using a computer's sound card.
.mp3 - This indicates a sound file that authentically reproduces voice and/or music. Windows Media Player will open and run this kind of file.
.scr - This indicates a screen saver file.
.sit - This indicates a Macintosh archive StuffIt file. A special utility is needed to open on a Windows system.
.ttf - This indicates a font designed specifically for use on a Windows system (True Type Font).
.txt - This indicates a plain text file that can be opened with Notepad.
.wav - This indicates a sound file similar to an .mp3 file but larger. Windows Media Player or Windows Sound Recorder supports these files.
.zip - This indicates a Windows archive WinZip file. They will not open on a Macintosh system without a special utility.
Gregg Hall is an author living on the Emerald Coast of Florida. Now that you know a little more about computers be sure that you get quality computer parts by going to http://www.nsearch.com