Playerbots

About 5,200 of the characters you meet are bots. They level from 1 to 80 across Azeroth, Outland and Northrend. They quest, talk in chat, and queue for the Dungeon Finder and battlegrounds, which is what fills those queues on a server this size.

They are not your companion. A companion belongs to you, lives on your account and has a personality and a memory. A bot belongs to the world: you can borrow one for a while, and it will go back to its own life afterwards.

Getting one into your party

Invite a bot the way you would invite a player. A bot of your own faction accepts as long as it is no more than five levels above you, and once it joins it is brought straight to you. Bots from the other faction refuse, even though players from both sides can group. The Dungeon Finder does the same job without the asking.

Telling it what to do

A bot in your party takes orders from party chat or a whisper. Type the word on its own. These are the ones you will use most:

follow	Stay with you.
stay	Stop where it is and wait.
summon	Teleport to you, if it is somewhere you are not.
attack	Attack your current target.
flee	Stop fighting and come with you. It stays out of fights until you say follow.

The same words work on your companion, because under the personality a companion is a bot too.