linux man page composition

    The online manuals for linux are very handy, but the documentation for some commands is very long and contains detailed descriptions for various situations. Although it is arranged in sections, many times we are only interested in some of the sections, and do not want to turn over the sections one by one. Therefore, in order to reduce the frequency of page turning, knowing the introduction scope of each subsection will help us quickly locate the corresponding command introduction.
    Linux man pages are generally divided into 9 sections, as shown in the following table:

Festival	content
1	User-level commands and applications
2	System calls and kernel error codes
3	library call
4	Device Drivers and Network Protocols
5	Standard file format
6	Games and demos
7	Various files and documents
8	system management commands
9	Rare and secret kernel specifications and interfaces

    Once you know what each section is about, the "man section command " allows the user to get the man pages from a particular section. For example, the "man tty" command gets the man page for the tty command, and the "man 4 tty" command gets the man page for the controlling terminal driver.