Making applications available to users is a major task for system administrators. Most users depend on reliable access to application software to get their jobs done. The demands of creating and maintaining user access to application software can easily consume a quarter or more of system administration time.
You may need to perform any or all of the following tasks to administer user access to applications.
Locate space for the software.
Install the software on multiple local systems or on an NFS server.
Set up user environments, such as paths, links, and environment variables that are specific to each application.
Revise user environments each time the software version changes or new software is added. ...