There are many online manual pages in UNIX for providing help on all commands. This how to is a guide to help you understand the online documentation, the man pages .
Most commands have a man page.
These instructions were written, for the most part, by programmers so there is usually more detail than the average person can use. But, if you want to know about a particular command in depth, use the man pages. Good reference books on UNIX are available locally at most bookstores and computer stores for people who prefer off-line help. To view a man page for a particular command, type man command. The instructions for the command will be displayed on your screen one page at a time.