what is a thriller?

A thriller can range from different genres they are commonly full of suspense which is the main feature of a thriller film. A thriller can often include over lapping genres to add to the tension and appeal to different audiences. Thrillers often have lots of fast paced action, the actions is usually frequent however in some thrillers suspense is used to build up tension before a piece of action. A typical thriller will have a very powerful and equipped villain that has plans that will effect lots of people, the hero or heroin will not be as prepared and must overcome lots of objects to defeat the villains plans. 
Many devices such as suspense, red-herrings and cliff hangers are used to add to the tension of a thriller. 
A thriller will often be non linear to make the audience wonder and think more about what is going on. Swordfish is a non linear film that makes you think of how they got to the point they are at. the film shows flashback of what is going on. 
The image below is one of the opening scenes from Swordfish, a bomb that was attached to a hostage has gone off and there in carnage on the streets surrounding where the other hostages are being kept.