What is a Thriller. What types of thriller are there?

Thrillers are usually defined by their main theme of Injustice Vs Justice, There uis also normally a price that must be paid to come to the conclusion of the story. Thrillers are usually done by point of view of either Hero, Villian or perhaps someone prosecuting the Law ie: A court room drama. The protaginist can normally have a minor and a major role in the plot and an oppisite for example in Sherlock Holmes, Sherlock is a major and his oppisite would be his nemisis Moriarty.

There are many different types of thriller Including Political in which the hero must ensure the stability of the government that employs him the success of such films like 'The Day Of The Jackal' Established the sub genre in the early 1960's.
In addition there are also Conspiricy Thrillers in which the hero confronts a large group of enemies, in which there true extent only he recognises. 'JFK' falls into this genre.
Another Type of Thriller would be a Physcological thriller this is where the conflict between main characters is more mental than physical, examples include 'Stranger on a Train' and 'Suspicion' both films by Alfred Hitchcock. And finally Horror Thrillers are quite wide in that they include elements from all other thrillers including mental,emotional and physical.
Other genres of thrillers are Spy, Military, Legal,Medical,Techno and Forensic.
People enjoy watching thrillers due to the fact that people in the modern western world have an attitude which means they can define the victims and feel empathy for that victim. it also means they are tempted to empahasise with an antagonist thrillers are meant to scare people because they know somethings going to happen but they can't do anything about it!