The level and significance of man query command in Linux system

1: User command, can be initiated by anyone

2: System calls, functions provided by the kernel

3: Library functions

4: Special files in device,/dev Directory

5: File format description, e.g./etc/passwd

6: Game

7: Miscellaneous, such as macro command packages, conventions, etc.

8: System administrator tool, only root boot

9: Other (Linux-specific) documents used to store kernel routines

N: New document, may be moved to a more suitable area

O: Old documents may be retained for a period of time

L: local documentation, related to this particular system

Detailed reference: http://blog.sina.com.cn/s/blog_4b9eab320101e8n2.html

The level and significance of man query command in Linux system