No, Unix certification is not required for all computer jobs, however it is useful to have some familiarity with Unix and all the different systems that computers run on. On top of that, you would also want to have a specialty in order to make more money.

See related link.

Directory tree structure in Unix always starts at the top node, or "root" node. It contains all of the major level subdirectories underneath it. The root directory is called "/" (root).

UUCP is the abbriviation of Unix to Unix copy. It is worldwide email system called UUCP or Unix to Unix copy.This email system was developed for the operating system called Unix.

No, but Linux is based on Unix since Linux is a Unix clone.