JavaScript Functions

What is a Function?

A function is a block of code that runs when it is called.

Functions help organize and reuse code.

Function Declaration

Parameters

Functions can take inputs called parameters.

Return Values

Functions can return values using the return keyword.

Function Expression

Arrow Functions

Arrow functions provide a shorter syntax.

Arrow Function with Return

Default Parameters

Calling Functions

Functions only run when they are called.

Full Example

Why Functions are Important

• Reuse code
• Keep code organized
• Solve problems step-by-step

Common Mistakes

• Forgetting to call the function
• Missing return statements
• Confusing parameters and arguments

Practice

Create a function that takes two numbers and returns their sum.

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