Rogue abilities are used in order to both deal damage and attempt to avoid it.
The majority of rogue abilities fall into one of three categories:
Opening moves - Openers are what every rogue should begin a fight with. These powerful attacks are only usable while [Stealthed] and break the Stealth effect upon use. A common tactic for burst damage is to open on the enemy, [Vanish], and open again. A few examples are [Ambush], [Cheap Shot], and [Garrote].
Combo moves - These moves are the bread and butter of a rogue. Combo moves generate Combo points, which are required to use a finishing move. They deal the majority of your damage and fill the void between your openers and your finishers. A few examples are [Sinister Strike], [Mutilate], and [Hemorrhage].
Finishing moves - These are the rogue's strongest attacks. They require Combo points to use and increase in effect depending upon the number of Combo points you have on the target. A good rogue will need to learn to use the right finishers at the right time, as there are a lot of them. A few examples are [Eviscerate], [Envenom], and [Rupture].
Note: Players technically start in Assassination spec; if a player chooses another specialization at level 10, Outlaw and Subtlety rogues lose Mutilate, Deadly Poison, and Envenom. Outlaw rogues also lose Evasion.