This is the 18th in a course of computer science video lessons introducing programming with Python. This lesson explains the difference between a sub procedure and a function. You will learn that, by definition, a function is a sub program that returns a value to the program that called it. The lesson begins with a review of procedure parameters. You will then meet the keyword return, which is all that is required to convert a procedure into a function. You also learn how to call a function and collect its return value. You will also see how a function call can be nested inside another function call.
Chapters:
00:00 Review of procedure parameters
02:25 Definition of a function
02:48 The return keyword
03:05 How to call a function
03:57 Nested function calls