Sequence diagram from UML 8/9 and SysML.Sentence diagram – represents the grammatical structure of a natural language sentence.Sankey diagram – represents material, energy or cost flows with quantity proportional arrows in a process network.Process flow diagram or PFD – used in chemical engineering.Pressure volume diagram used to analyse engines.Phase diagram used to present solid/liquid/gas information.Piping and instrumentation diagram (P&ID).Phylogenetic tree - represents a phylogeny (evolutionary relationships among groups of organisms).Petri net – shows the structure of a distributed system as a directed bipartite graph with annotations.Onion diagram – also known as 'stacked Venn diagram'.O–C diagram – a diagnostic plot of observed minus predicted values over time.Nassi–Shneiderman diagram or structogram – a representation for structured programming.Mind map – used for learning, brainstorming, memory, visual thinking and problem solving.Interaction overview diagram – from UML.Internal block diagram (IBD) used in SysML.Goodman diagram – shows the fatigue data (example: for a wind turbine blades).Gantt chart – shows the timing of tasks or activities (used in project management).Extended functional flow block diagram (EFFBD).Eye diagram – a diagram of a received telecommunications signal.

Composite structure diagram – from UML 2.0.

Block definition diagram (BDD) used in SysML.

Activity diagram used in UML 6/9 and SysML.

: 48 A diagram may act as a means of cognitive extension allowing reasoning to take place on the diagram based on which constraints are similar. On the other hand the representation of an object in a diagram may be overly specific and properties that are true in the diagram may not be true for the object the diagram represents. Sometimes certain geometric properties (such as which points are closer) of the diagram can be mapped to properties of the thing that a diagram represents. This is related to the concept of isomorphism, or homomorphism in mathematics. : 42 Structural similarity can be defined in terms of a mapping between parts of the diagram and parts of what the diagram represents and the properties of this mapping, such as maintaining relations between these parts and facts about these relations. Rather a diagram may only have structural similarity to what it represents, an idea often attributed to Charles Sanders Peirce. Scholars note that while a diagram may look similar to the thing that it represents, this is not necessary. Diagrammatology ĭiagrammatology is the academic study of diagrams. Elegance is basically determined by whether or not the diagram is 'the simplest and most fitting solution to a problem'. The basic shape according to White (1984) can be characterized in terms of 'elegance, clarity, ease, pattern, simplicity, and validity'. These simplified figures are often based on a set of rules. Or in Hall's (1996) words 'diagrams are simplified figures, caricatures in a way, intended to convey essential meaning'. with building blocks such as geometrical shapes connected by lines, arrows, or other visual links.a display that does not show quantitative data (numerical data), but rather relationships and abstract information.The essence of a diagram can be seen as: In the specific sense diagrams and charts contrast with computer graphics, technical illustrations, infographics, maps, and technical drawings, by showing 'abstract rather than literal representations of information'. On the other hand, Lowe (1993) defined diagrams as specifically 'abstract graphic portrayals of the subject matter they represent'. For example, Anderson (1997) stated more generally: 'diagrams are 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'. In science the term is used in both ways. specific kind of visual display : This is the genre that shows qualitative data with shapes that are connected by lines, arrows, or other visual links.visual information device : Like the term ' illustration', 'diagram' is used as a collective term standing for the whole class of technical genres, including graphs, technical drawings and tables.The term 'diagram' in its commonly used sense can have a general or specific meaning: The word graph is sometimes used as a synonym for diagram. Sometimes, the technique uses a three-dimensional visualization which is then projected onto a two-dimensional surface.

Diagrams have been used since prehistoric times on walls of caves, but became more prevalent during the Enlightenment. Further information: ChartĪ diagram is a symbolic representation of information using visualization techniques. For other uses, see Diagram (disambiguation).

Types of diagrams and charts