Understanding Genre

My definition of Genre is style. For example style of movies: thriller, action, comedy and romance.
style of music: rock, classical and indie.

Google's definition of "Genre". 

• A category of artistic composition, as in music or literature, characterized by similarities in form, style, or subject matter.

Thriller.

This is a genre which have main elements of suspense or excitement. This makes the view have ideas of uncertainty. But main genres have sub-genres and thriller has many, here's a few examples: 

• Physiological thriller.
• Period thriller.
• Mystery thriller.
• Crime thriller.
• Paranoid thriller.

Iconography (symbols or images)  of a thriller:

• Shadows.
•  Confined spaces.
• Dim street lamps.

Narrative:

• A death (Suicide, pre-determined, accidental).
• Some being watched/followed.

Mise-en-scene:

• Lighting would be mainly dark but bright on points of interest.
• Colours mainly black and grey's.
• Clothing would depend on time and location. Usually dark alleys and strange and large buildings.
• Facial expressions typically scared with the victim and the villain would show a black expression.
• Camera angles and technique. Camera angles could be in a view of a security camera, and tracking could be used with shaking behind victim is running away from villain.

Themes of a thriller:

• Revenge.
• Isolation from the outside world.
• Slight chance of sexual perversion.

Representations portrayed in movies such as thrillers:

• Sexism (Girl have to be fragile and men have to be heroic).