Many of the programs that drive crystallographic data collection and reduction through to a structure solution operate on computers that are UNIX / LINUX based. As a result, many operations can be done from a terminal window using UNIX / LINUX commands. Many systems use RedHat Linux, and others use CentOS Linux. There are many versions of UNIX / LINUX in use, and many Structural Scientific GUI programs use a LINUX platform to serve up their program to the user. Often the GUI programs are clunky at moving files etc. which can often be done easily at a terminal window with a bit of UNIX / LINUX command line knowledge.