This article explains what a Z file is, how to open it on your computer, and how to convert it to another format.
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A file with the Z file extension is a Unix compressed file. Like other archive file formats, it is used to compress a file for backup/archiving purposes. However, unlike more complex archives, Z files can only store a single file and not directories.
.z files (lowercase Z) are GNU compressed files, while .Z files (uppercase) are compressed using the compress command in some operating systems.
GZ is an archive format somewhat similar to this format and is more common on Unix systems, while Windows users often see similar archive files in the ZIP format.