Symbolism 

Symbolism is the use of signs to create meaning. It involves consideration of:

  • which images are chosen and what they stand for
  • where they’re placed and the hierarchy of relationships between each of the signs.

Placing something at the front or top of an image will create a different meaning from placing something at the back or bottom.

See Research point: William Hogarth

Semiotics (to be developed)

Wikipedia

Semiotics is branch of linguistics that studies how we read signs. It is useful to illustrators to have some grounding in semiotics as it provides a technical language to describe how images are coded and decoded. Amongst other concepts semiotics uses connotation and denotation
as a way of describing actual and intended meanings:

  • Denotation describes the obvious, literal things in an image.
  • Connotation describes the associations we have with that image. These associations are determined by our social, economic and personal perspectives.
 This post needs much more development