What command is used to compress files using gzip?

The command used to compress files using gzip is indeed "gzip." Gzip is specifically designed to reduce the size of files, especially text files, by employing the DEFLATE compression algorithm. When you use the gzip command followed by the name of the file, it compresses that file and typically adds a ".gz" extension to it, indicating that the file is now compressed.

For instance, issuing the command gzip filename would result in a compressed file named "filename.gz." This makes it easy to identify which files have been compressed.

While there are other commands related to file compression, they serve different purposes or use different methods for compression. The "zip" command, for example, compresses files into a zip archive, which is a different format. The "tar" command is primarily used for archiving multiple files together into a single file (tarball), and it does not perform compression by itself, though it is often used in conjunction with gzip or bzip2 for compressing those tarballs. Similarly, the "compress" command used a different compression algorithm and is less commonly utilized today than gzip.

Thus, "gzip" is the correct answer for compressing files using the gzip algorithm.