Introduction to Built-in and User-Defined Functions

Python provides a rich set of built-in functions that simplify common tasks. Additionally, you can create your own custom functions, called user-defined functions, to suit specific needs.

In this lesson, you will learn the differences and use cases for built-in and user-defined functions.

What Are Built-in Functions?

Built-in functions are predefined functions that are always available in Python. They perform common tasks and don’t require additional code to use. Examples include:

• print(): Outputs text to the screen.
• len(): Returns the length of a collection.
• type(): Returns the type of a variable.