How Linux shuts down at the command line (terminal) ____linux

Learn Linux and Oracle on the virtual machine, because often use the terminal, originally always is to shut down the terminal first, then "system"-"shut down", continue the way of windows; feel very inconvenient, checked the command of the Shimonoseki: shutdown-?

Halt-?

Reboot-?

Did not understand, direct experiment, finally shutdown-h now executed successfully. (never understood the meaning of the shutdown-h (or P) Now command, and the screen stays in the sh-3.1# state after executing the command)

RELATED Links: http://www.linuxdiyf.com/bbs/viewthread.php?tid=153611&extra=&page=1

Add: Stay in the sh-3.1# interface, Linux into Single-user mode, then execute shutdown-h now can be shut down (in fact, just start on the command line directly to execute it)