Composition Definition:

 In art composition is the way paintings, photos etc are made up.

Google definition-

the nature of something's ingredients or constituents; the way in which a whole or mixture is made up.

• 
  
• the action of putting things together; formation or construction.
• 
  
• a thing composed of various elements.

  
  
• mental constitution; character.

  
  
• a compound artificial substance or material.