Context Models - What They Do and Don't Show

(1) Context models show which external systems are in the environment of the system being specified

(2) Context models are used to define system boundaries - what is and is not part of the system

(3) Context models are normally used alongside process models to give a more complete picture

Explanation

Context models show which external systems exist in the environment and define the system boundary. They do NOT show the precise nature of relationships between systems (whether data is shared, consumed, or produced) - this requires process models or other diagrams. Context models also do not show internal components - that is the role of structural models.