This package provides the x86 disk image of FreeBSD 10.1. The image can be written to fixed or removable media such as a hard disk or USB drive. It is compressed in an .xz archive for a smaller download.
This is the original file available from https://www.freebsd.org/.
If you are using a Windows system and don't know how to extract the contents of an .xz archive try 7-zip (http://www.7-zip.org/).