Computational constructs or components which are not broken down (in a given context, such as a programming language).
What?
I'm not sure what the original poster intended, but here's what I think of when I hear of computation primitives:
Imperative language primitives:
object-oriented language primitives:
LogicProgrammingLanguage primitives:
functional language primitives:
relational language primitives:
Digital logic primitives: