View parameters for a command under Linux

1, generally each command with the help parameter, using the following methods:

Shutdown--help

Tip: Shutdown is a shutdown command that requires root privileges for real-world use, such as sudo on the front.

2, use the Man command to view, using the following methods:

Mans shutdown

At this point will go into a detailed interface, described here in very detailed, page flipping using the up and down keys, quit using "Ctrl + Z".

View parameters for a command under Linux