Linux command format and help commands

Yesterday I saw a tutorial, aboutLinuxCommand, originally thought that when is review casually to look at, the result looked can not help but ashamed, this really has learned, many things are I do not know, therefore summarizes, this article is suitable for the Linux command to have certain understanding but is not very deep child, if is the initial contact Linux command is not suitable ~ ~

Linux commandsformat：
command [options] [arguments]
Command: Commands
Options:--words or-word
such as: LS--all
Equ ls-a
Ls-a-b-c
Equ LS-ABC
Argument: parameter (file name or other)

When you view the command help, symbols such as [],<>,|] appear, meaning the following:
[] the expression is optional;
<> the expression is changeable;
X|y|z indicates that onlySelectA
-ABC represents a mixed use of three parameters (or any two)

Help command:
Whatis <command>: Show Short function description

<command>--help: Show usage Summary and parameter list (you can see the usage of most commands)

man [<chapter>] <command>: View command description or manual page (Manual)
Note: descriptionfileare divided into different pages, the man command is to view these pages
Manual Sections
1:user commands (*) 4:special files 7:miscellaneous
2:system calls 5:file formats 8:administrative commands (*)
3:library calls 6:games
Bottom line under the Man commandMode：
/<text> Find Keywords
n/n Next/Previous
Q Leave
Man-k <keyword> List of man pages with keyword keywords

Info <command>: View command Detailed documentation
NOTE: info looks at a more detailed description than man, which is to divide the man's page into smaller chapters.
This command can also be linked to similar topics
Info command Bottom-line mode:
Arrows.pageUp.pageDown switching
Tab Jump down a link (where there is *)
Enter Enter link
N/p/u Jump down One (previous) section, previous section
S[<text>] Find keywords
Q Leave


<command>--?

usr/share/doc/Description File Directory
http://www.redhat.com/docs/online documentation

Linux command format and help commands