A cpio archive is a stream of files and directories in a single archive, and often ends with a .cpio file extension. The archive has header information that allows for an application such as the [[GNU_cpio]] tool to extract the files and directories into a file system. The header of a cpio archive also contains information such as the file name, time stamp, owner and permissions.

=== Example use ===
If you wanted to archive an entire directory tree, the find command
can provide the file list to cpio:

 % find . -print -depth | cpio -ov > tree.cpio

Cpio copies files from one directory tree to
another, combining the copy-out and copy-in steps without actually
using an archive.  It reads the list of files to copy from the standard
input; the directory into which it will copy them is given as a
non-option argument. 

 % find . -depth -print0 | cpio --null -pvd new-dir

To extract files from a cpio archive, pass the archive to cpio as its standard input.

 cpio -id < cpiofile

The -i flag indicates that cpio is reading in the archive to extract files, and the -d flag tells cpio to construct directories as necessary. You can also use the -v flag to have file names listed as files are extracted.