Definition of 'Thriller'

I thought it be helpful to define what the thriller genre is as it's not as clear cliched as other film types. I also wanted to distinguish the the thin line between the horror and thriller genre. The thriller genre, although showing similar traits to Horror is far more subtle focusing on stimulating the viewer's moods inducing high levels of anticipation, anxiety, uncertainty and in some cases terror without revealing clearly what it is to be frightened of- unlike horrors where there is clear gore and the enemy tends to be unmasked. Psychological thriller is a specific sub genre of the broad ranged thriller that's becoming increasingly popular, it's focus is on the unstable emotional states of characters an example is one of my favorite films, Silence of the Lambs.