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This is the first in a series introducing the activity model in the Unified Modeling Language, version 2 (UML 2), and how it integrates with the action model [1]. The series is a companion to the standard, providing additional background, rationale, examples, and introducing concepts in a logical order. This article covers motivation and architecture for the new models, basic aspects of UML 2 activities and actions, and introduces the general notion of behavior in UML 2.
Bock, C.
(2003),
UML 2 Activity and Action Models, Journal of Object Technology, [online], https://doi.org/10.5381/jot.2003.2.4.c3
(Accessed October 8, 2025)