Here's a list of the basic commands. You can also find this information in-game by typing "/help".

/help - Display the help information in-game. Addintionally there are several commands for help
/spawn - Returns your player to the spawn point.
/trade - Brings your player to the public, secured, trading area. Additionally typing /trade again will return your player to the last known location.
/msg <name> <message> - Sends a private message to the specified player.
/server Displays the server health and number of players online.
/server players - Displays a list of all online players.
/sethome - Sets a home location for your user.
/home - Returns you to your home location.
/compass - Displays the direction you are facing.
/chat - Turns the public chat on or off.
/online <name> - Displays if a user is online or offline.

--

If you're new to minecraft, make sure to check out this tutorial:
http://www.minecraftwiki.net/wiki/Tutor ... er's_guide

If you're looking for information regarding the realm commands [Survival Server], look here:
http://minerealm.com/c//v/1455

For server information, go here:
Survival: http://minerealm.com/c/v/119
[DISCONTINUED]Creative: http://minerealm.com/c/v/790

Does this mean that /playerlist no longer works? :O

Either one works.

What about /online I use that don't why but it works

Added to the list.

how do u check the map? is there even a map?

On the site's homepage, under "Useful Stuff" click "World Map". It's located on the left of the page.

what about invisible leader?