Kill Camera

Finishing moves are a mechanic-feature introduced in The Elder Scrolls V: Skyrim that allows the player to kill enemies with a final deadly strike.

Overview
While performing a finishing move a short animation is played, making the player vulnerable to attack and unable to carry out any other task for a couple of seconds until the animation has played through. Finishing moves also depends on the position of the enemy in relation to the character, upon attacking. For instance, striking an enemy from the flank or behind produces different finishers than a strike met head-on. Bound Sword and other Conjured weapons produce finishers.

Noted that enemies can perform finishing move too, if the player's hp is low enough and the enemy damage high enough (You can be executed by a finishing move with full HP. The exact damage/hp ratio is currently unknown).

It is also possible to use a finishing move on an enemy with full health, although this is unlikely unless the character vastly outclasses the opponent or is doing a backstab attack with the Assassin's Blade perk.

Performing a finishing move can happen randomly in a fight but can be done on command by tapping R1 and flicking the left analog stick forward (PS3)

For the Xbox to perform a finishing move on command is done by tapping RT and moving the left stick forward at the same time. (Xbox 360)