Summary  
This chapter explains how to define and call functions to group reusable blocks of code, reducing repetition and improving code readability.

General domain of usage  
User interaction (e.g., greeting users)

## Why Use Functions?
Repeating the same code makes your programs long, harder to read, and difficult to update. Functions let you group commands into a reusable block, reducing repetition and keeping your code clean.

To **call** a function, write its name followed by parentheses. If the function requires arguments, place them inside the parentheses. For example:
```javascript
greet("Alice")
```


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Learn to control the ninja using simple JavaScript commands. Move in different directions to navigate the grid. Pick up sushi by calling predefined actions. Solve small missions that reinforce sequencing and basic code execution.

Use movement commands to navigate more complex layouts. Pick up sushi and place it on specific cells. Combine movement and object manipulation to transport sushi across the grid. Solve multi-step missions that require planning, precision, and full control of the ninja's actions.

In the "Functions" section, you'll delve into the powerful JavaScript feature of creating and utilizing functions to streamline your code. You'll learn how to write functions to perform specific tasks, enhancing code reusability and clarity. By practicing decomposition, you'll break down complex problems into simpler functions, mastering the art of organized and efficient coding.

In the "Loops" section, you'll explore the essential JavaScript feature of loops, which allows you to execute repetitive tasks efficiently. You'll learn to implement both for loops and while loops, gaining the ability to automate actions and iterate over sequences. By mastering nested loops, you'll tackle more complex scenarios, enhancing your ability to write concise and powerful code.

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Using Functions

Why Use Functions?

Solution