Inheritance in PHP (Extend Classes Correctly)

Inheritance allows a class to extend another class.

Example: base class + child class

```php <?php class Employee { public function __construct(public string $name) {}

public function role(): string { return "Employee"; } }

class Manager extends Employee { public function role(): string { return "Manager"; } }

$e = new Employee("David"); $m = new Manager("Sarah");

echo $e->role(); // Employee echo $m->role(); // Manager ?> ```

When inheritance is useful

- you have a strong "is-a" relationship - Manager is an Employee

When to avoid

If you are just sharing code but relationship is not clear, composition (using another class inside) is often better.

> Next: Interfaces, building flexible and testable code.