Free Programs

7-Zip

It's easy for Windows users to forget that WinZip isn't the only file-compression utility in the world. Like its better-known competitors, the free 7-Zip unpacks a host of archive formats, including ZIP, TAR, GZ, and its own 7z format. Unlike WinZip, though, it can create TAR and GZ archives, which are commonly used on Unix and Linux systems.

The program's ability to shrink files was stunning. In our tests, 7z archives were up to 40 percent smaller then their ZIP equivalents, although compression did take longer, and the highest compression settings can hog system resources. Advanced options include the ability to create solid and self-extracting archives, and to adjust the compression level and password protection.