I\'m asking with regards to c#, but I assume its the same in most other languages.
Does anyone have a good definition of expressions and statements
For an explanation of important differences in composability (chainability) of expressions vs statements, my favorite reference is John Backus's Turing award paper, Can programming be liberated from the von Neumann style?.
Imperative languages (Fortran, C, Java, ...) emphasize statements for structuring programs, and have expressions as a sort of after-thought. Functional languages emphasize expressions. Purely functional languages have such powerful expressions than statements can be eliminated altogether.