Functions
In this section you’ll learn how to define and call functions, pass them data with parameters and arguments, and get results back with return values.
What are functions?
A function is a reusable block of code that does one job. You give it a name, and whenever you need that job done, you call the function. Functions help you:
- Organize your code
- Make it more readable
- Avoid repetition
Defining a function
You define a function using the def keyword, then the name you want for the function, then parentheses. When you define a function, you’re writing the code that will run later when you call it.
Here’s a simple function that greets a user:
def greet():
print("Hello, welcome to Python!")We defined a function named greet that prints a welcome message when you call it.
Calling a function
To call a function, use its name followed by parentheses:
greet() # Output: Hello, welcome to Python!When you call a function, the code inside it is executed. So calling greet() runs that code and prints Hello, welcome to Python! to the console.