These are not binaries that the typical user will be using. Instead, these are the programs that the system administrator will use to make the computer operate efficiently . This directory contains files that ordinary users need access to. This accounts for some of the structural duplication. The var directory The var directory contains data that vary.
Data change rapidly in some active systems on the computer.
A job to be printed may stay in the spooler for just a few minutes. Once the job is printed, it's deleted from the print spool. Electronic mail is also kept in a spool file until the intended recipient retrieves it. Mail may be added and deleted from the mail spool at any time. Data like these are generally short-lived.