A new Facebook app called EnemyGraph hit the Web this week, and it gives Facebook users a way to express their strong dislike of people and things.

The app was created by a professor at the University of Texas-Dallas, Dean Terry, and some students. Terry has said that Facebook offers a lot of information about users "likes", interests and preferences. But he wanted to build an app that helped users track things they don't like.

Hence, EnemyGraph.

Watch the video for a quick walk-through on how it works.