Structural decomposition
1. Structures are physical components, logical objects, attributes, fields, or arrangements of other structures within a design.
2. Structures typically answer the question of “what”
3. Typically described using nouns and adjectives.
Behavioral decomposition
1. Behaviors are an action, force, process, or control that is exerted on or by a structure with respect to the structure's external environment.
2. Behaviors typically answer the questions of “how” and “when”.
3. Typically described using verbs and adverbs.