命令格式怎样看？

[SKY11]

NET USER [username [password | *] [options]] [/DOMAIN] username {password | *} /ADD [options] [/DOMAIN]
username [/DELETE] [/DOMAIN]

　好象这些命令格式应该怎样看呀，[]　｜　这些东东怎样搞清楚的，谁能帮我认真解答下吗？

　　　　　　　　　　　　　　　　　　　　　先谢为过！

[sink]

net user /?

[sungod8]

NET USER
[username [password | *] [options]] [/DOMAIN]
username {password | *} /ADD [options] [/DOMAIN]
username [/DELETE] [/DOMAIN]

NET USER creates and modifies user accounts on computers. When used
without switches, it lists the user accounts for the computer. The
user account information is stored in the user accounts database.

username Is the name of the user account to add, delete, modify, or
view. The name of the user account can have as many as
20 characters.
password Assigns or changes a password for the user's account.
A password must satisfy the minimum length set with the
/MINPWLEN option of the NET ACCOUNTS command. It can have as
many as 14 characters.
* Produces a prompt for the password. The password is not
displayed when you type it at a password prompt.
/DOMAIN Performs the operation on a domain controller of
the current domain.
/ADD Adds a user account to the user accounts database.
/DELETE Removes a user account from the user accounts database.

Options Are as follows:

Options Description
--------------------------------------------------------------------
/ACTIVE:{YES | NO} Activates or deactivates the account. If
the account is not active, the user cannot
access the server. The default is YES.
/COMMENT:"text" Provides a descriptive comment about the
user's account. Enclose the text in
quotation marks.
/COUNTRYCODE:nnn Uses the operating system country code to
implement the specified language files for a
user's help and error messages. A value of
0 signifies the default country code.
/EXPIRES:{date | NEVER} Causes the account to expire if date is
set. NEVER sets no time limit on the
account. An expiration date is in the
form mm/dd/yy(yy). Months can be a number,
spelled out, or abbreviated with three
letters. Year can be two or four numbers.
Use slashes(/) (no spaces) to separate
parts of the date.
/FULLNAME:"name" Is a user's full name (rather than a
username). Enclose the name in quotation
marks.
/HOMEDIR:pathname Sets the path for the user's home directory.
The path must exist.
/PASSWORDCHG:{YES | NO} Specifies whether users can change their
own password. The default is YES.
/PASSWORDREQ:{YES | NO} Specifies whether a user account must have
a password. The default is YES.
/PROFILEPATH[:path] Sets a path for the user's logon profile.
/SCRIPTPATH:pathname Is the location of the user's logon
script.
/TIMES:{times | ALL} Is the logon hours. TIMES is expressed as
day[-day][,day[-day]],time[-time][,time
[-time]], limited to 1-hour increments.
Days can be spelled out or abbreviated.
Hours can be 12- or 24-hour notation. For
12-hour notation, use am, pm, a.m., or
p.m. ALL means a user can always log on,
and a blank value means a user can never
log on. Separate day and time entries with
a comma, and separate multiple day and time
entries with a semicolon.
/USERCOMMENT:"text" Lets an administrator add or change the User
Comment for the account.
/WORKSTATIONS:{computername[,...] | *}
Lists as many as eight computers from
which a user can log on to the network. If
/WORKSTATIONS has no list or if the list is *,
the user can log on from any computer.

[spark_li]

net help user

至于
NET USER [username [password | *] [options]] [/DOMAIN]
username {password | *} /ADD [options] [/DOMAIN]
username [/DELETE] [/DOMAIN]

怎么解释：
其中第一行是命令的格式，
第二行和以后的是对命令的详细的（各个选项）的解释，
这里呢，[]里面的内容是可选项，{}里面的是必选项，
|分开的呢表示可选择|前面的，也可以选择后面的，

正对以上命令，第一行：
首先是net user 必须，后面的有三个可选项
分别是：
[username [password | *]
[options]]
[/DOMAIN]
因为是可选项，所以我们用net user 也是正确的命令格式，
这里[username [password | *]
是双重[]，所以可以
net user username
net user username password
net user user *
其中password与*用|分开，说明他们是任选项
后面的就差不多了

至于net help user是更详细的解释，
主要是解释各个命令格式是做什么用的。