1 2 3 4 5 6 7 8

Indicates Graphics Interchange Format -- a type of graphic image very common in online services and the Internet. GIF includes file compression as part of its definition, so no additional file compression software is needed
.jpg or .jpeg
Indicates Joint Photographers Experts Group -- a graphics format designed to take up as little space as possible while retaining as much quality as possible. JPG files are smaller than GIF files, but take longer to display. AOL's software will display these.
This file extension tells you to do something. For example, files named read.me usually contain last- minute instructions and updated information. .mid (.midi)
Indicates a Musical Instrument Digital Interface file. MIDI files are songs for most sound cards and MIDI boards. Apple's new QuickTime 3 will play these. .mme and MIME
Indicates a Multipurpose Internet Mail Extensions (MIME) file. MIME converts a binary attachment (a program or word processing document or even an image) to a text format that can be handled by the machines that send e-mail through the Internet. The Internet's e-mail system handles basic text files nicely, but doesn't always handle binary files like pictures or word processing documents. So, when you send an e-mail message with a file attachment to someone on the Internet that can't handle binary files, either AOL or your e-mail client will sometimes encode or translate the attachment using MIME. Macintosh users can use utilities such as Decoder , Mpack , or Stuffit Deluxe to easily decode MIME files. You can download Decoder from:
http://www.concentric.net/~Columbin/. Mpack (a better utility) can be obtained from:
Indicates a music module. These are music files that include the instruments as well as the score, and they play through a sound card, not MIDI. You will need a special program to play these files, such as SoundApp. .pcx
Indicates older Windows graphics files, commonly used for clip art.

.pct or .pict
Indicates the original Macintosh graphics format. Even SimpleText can open them.
Indicates a self extracting archive -- a type of compression file. These are Macintosh Stuffit self- running files that, when launched, expand into several smaller files. They cannot be used in Windows. .scr
Indicates a Windows screen saver file.
Indicates a StuffIt file. These are Macintosh
compressed files that can be extracted by Windows users with programs such as UnSit and UnStuff. Some of the files with this extension will not run on Windows, even after extraction.
Indicates a sound file. These are Macintosh System 7 sounds that can be played by simply double-clicking them and can be opened in any Mac sound utility. They can also be played on Windows using converters such as SOX.
Indicates a Tagged Image Format -- bitmapped graphic images popular among desktop publishers. Also known as TIFF.
Indicates a True Type Font. These are scalable fonts commonly used in Windows, but may also run on Macintosh.
Indicates a text file. These are usually just plain text that can be read by most programs, especially Notepad  on Windows, and SimpleText , on Macs. AOL's software will display these if they are 16K or less in size.
Indicates a Windows sound file. Mac users can use utilities such as SoundApp to play them, and also convert them to Mac sound formats.

Indicates a PKzip archive. This is the most common format for compressed files in the Windows world. Use ZipIt to create and decode them on the