In an effort to show off the options a player will have to solve different problems they are faced with in Deus Ex: Human Revolution, Eidos and Square Enix have put together a video that shows three different ways that the first mission in the game can be completed. Obviously watching the video will show you how to complete the first mission and will contain spoilers as to what happens.
The first run through consists of Adam using everything in his arsenal to kill the people in his path while the second playthrough is more stealthy and involves Adam sneaking around to avoid combat and hiding from enemy eyes. Finally the last route involves avoiding the main entrance entirely and going through a secondary entrance. The variety shown off in this video makes it so that no matter how you play, you will be able to advance through the story when the game arrives on consoles and PC on August 23rd in the U.S.