Functions let you reuse code instead of repeating it.
  
  ## Simple function
  
  ```php
  function greet() {
    echo "Hello!";
  }
  
  greet();
  ```
  
  ## With parameters
  
  ```php
  function greetUser($name) {
    return "Hello $name";
  }
  
  echo greetUser("Daniel");
  ```
  
  ## Default values
  
  ```php
  function greetUser($name = "Guest") {
    return "Hello $name";
  }
  ```
  
  ## Type hints (modern PHP)
  
  ```php
  function add(int $a, int $b): int {
    return $a + $b;
  }
  ```
  
  > Next: Variable scope and global variables.

Create reusable blocks of code using PHP functions with parameters and return values.

Functions in PHP

Learn PHP programming for server-side web development. Master PHP syntax, functions, and building dynamic websites.

Functions in PHP

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