Diagrams, Graphs and Charts

A diagram is a two-dimensional geometric symbolic representation of information according to some visualisation technique. Sometimes, the technique uses a three-dimensional visualisation which is then projected onto the two-dimensional surface.


• Pictorial, yet abstract, representations of information, and maps, line graphs, bar charts, engineering blueprints, and architects' sketches are all examples of diagrams, whereas photographs and video are not
• Abstract graphic portrayals of the subject matter they represent
• Abstract rather than literal representations of information
• Simplified figures, caricatures in a way, intended to convey essential meaning
• Simplest and most fitting solution to a problem


The essences of diagram:

• a form of visual formatting devices
• a display that do not show quantitative data, but rather relationships and abstract information
• with building blocks such as geometrical shapes connected by lines, arrows, or other visual links

A chart is a graphical representation of data. Data is represented by symbols. A chart can represent numeric data, functions or some kinds of qualitative structures.


A graph is an abstract representation of a set of objects where some pairs of the objects are connected by links.