The man pages are UNIX on-line help. They contain almost everything to define how UNIX works, but are often terse, precise, and obscure.
Examples are rare.
Some topics are difficult to find because they are features of a shell program, such as the else command of the ksh shell, rather than functions of basic UNIX itself. The man pages are divided into sections and the same topic can occur in several sections of the man pages. The sections are based on historical accident and are not that consistent.