Noun

(en noun)

A plan, drawing, sketch or outline to show how something works, or show the relationships between the parts of a whole.

*{{quote-magazine, date=2012-03

, author= , title=Pixels or Perish , volume=100, issue=2, page=106 , magazine= citation , passage=Drawings and pictures are more than mere ornaments in scientific discourse. Blackboard sketches, geological maps, diagrams of molecular structure, astronomical photographs, MRI images, the many varieties of statistical charts and graphs: These pictorial devices are indispensable tools for presenting evidence, for explaining a theory, for telling a story.}}

Electrical diagrams show device interconnections.

A graph or chart.

(category theory) A functor from an index category'' to another category. The objects and morphisms of the index category need not have any internal substance, but rather merely outline the connective structure of at least some part of the diagram's codomain. If the index category is ''J'' and the codomain is ''C'', then the diagram is said to be "of type ''J'' in ''C ".