If you're a PC user, you would be well-served to get the program WinZIP, which can handle a wide range of common archive formats. Macintosh users would do well to get Stuffit Expander, which also has a companion suite called Expander Enhancer to handle most of the formats you'd find on the net. Windows 95 and NT 4.0 users may want to look at VisualZIP Pro32. Addresses of sites from which these programs can be downloaded are available at the end of this document.
.Z- Compressed with the standard Unix
compressutility. To handle this file use
uncompressif you're on a Unix system. Use
WinZipon a PC. StuffIt Expander with Expander Enhancer will handle it on a Macintosh. It's possible that
gunzipwill handle this as well, but I'm not 100% sure of that.
.zip- Zipped file (compressed with a utility like PKZIP. On a PC, unpack using PKZIP, gunzip, WinZIP, or similar utility. On a Unix host, unpack using gunzip. On Macintosh, try StuffIt Expander.
.gz- Gnu Zip format. Unpack using gunzip on Unix systems, "macgzip" on Macintoshes, or WinZIP on PCs.
.sit- StuffIt file (compressed with StuffIt)---a popular Macintosh compression scheme. Widely understood by compression programs other than StuffIt.
.cpt- Compactor Pro file (another popular Macintosh compression program).
.exe- Runnable file. Often a SEA file.
.sea- Self-Extracting Archive. This file is runnable and will automatically unpack itself along with any supporting files.
.tar- Unix tape archive file (tar). Unpack on a Unix system using a command like "tar -xvf filename". Macintosh users can handle these with a utility called "Tar" and PC users can handle them with WinZIP.
.uu- UUencoded file. This format takes a binary file and converts it to an ASCII representation that can be sent through E-mail or Usenet news. Can be decoded under Unix using a command like "uudecode filename". Mac users can decode using UU Undo. PC users can decode using WinCode.
.hqx- Binhex format. Commonly used in the Macintosh community to take a binary file and convert it to an ASCII representation. Can be decoded using BinHex 4.0 or StuffIt Expander. PC users can often decode these using BinHex 13.
.ps- PostScript file. This is a widely-used page description language developed by Adobe. It is built into most high-end laser printers made in the last 10 years and most users can simply send a file to a PostScript printer. PostScript can also be viewed onscreen using a viewer like Ghostscript. Ghostscript is a free utility that is available for Unix, Macintosh, and PCs. Macintosh users can print using Laserwriter Font Utility. Commercial packages like Freedom of Press may be able to handle on PCs and Macintoshes.
.tex- This is a TeX or LaTeX file, a document description language developed by Donald Knuth at Stanford University. It is widely used in the mathematics and some other science fields. To use the files, you'll need a complete TeX and LaTeX installation along with supporting utilities. Free software is widely available for most platforms, although I haven't seen a robust public-domain TeX for the PC.
.gif- GIF image. Handled by most browsers. Can be displayed by most image viewers. Use xv on Unix hosts.
.jpeg- JPEG image. Displayed in Netscape, but not always by other viewers. Usually more compact than equivalent GIFs. Can be viewed by a wide range of external graphic viewer programs.
.tiff- Tagged Image Format File. Commonly produced by scanners. Can be viewed by some external viewer programs and can often be imported into page layout programs.
.mpeg- Movie/animation file.