Functions

Functions: Custom-made functions   cf) built-in functions

• Make your own functions and play with it like Lego block.
• Clients don't have to know what's inside the block. If the block is what you want, you can use it without knowing how it is structured inside.
• Functions are composed of primitive calculations and algorithms. However, from a broad view, functions become primitive calculations that belong to broader algorithms.

Expressions: Everything that returns value.   cf) statements

source: https://docs.python.org/2/glossary.html

Control:

Invocation: invoke = call