You've learned functions. Here's what we covered: Defining functions with def and calling them with parentheses
Parameters (placeholders) and arguments (actual values)
Return values vs printing
Default parameters and keyword arguments
Variable scope (local vs global)
Lambda functions for quick one-liners Functions are the building blocks of organized code. Every program you write from now on should use them. In the next section, you'll learn dictionaries, Python's key-value data structure. Combined with functions and lists, you'll have the tools to build real programs.