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:
- sequence
- selection
- iteration
object-oriented language primitives:
- send
- receive
- ...
LogicProgrammingLanguage primitives:
- ...
- matching
- unification
- ...
functional language primitives:
- ...
- transform
- ...
relational language primitives:
- ...
Digital logic primitives:
- NAND
- wires