What is object-oriented programming (OOP)?

OOP is a programming paradigm based on the concept of "objects" that can contain data (properties) and code (methods).

Main principles of OOP:

• Encapsulation: Combining data and methods that work with them into a single entity (class/object) and hiding internal implementation from the outside world.
• Inheritance: The ability to create new classes (subclasses) that inherit properties and methods from existing classes (superclasses), extending or overriding their functionality.
• Polymorphism: The ability to use objects of different classes with the same interface, allowing them to be processed uniformly.
• Abstraction: Highlighting important characteristics of an object and hiding non-essential details to simplify modeling.

Example of a simple class in PHP:

<?php

class Car {
    // Property (data)
    private $model;

    // Constructor (initialization of the object)
    public function __construct(string $model) {
        $this->model = $model;
    }

    // Method (functionality)
    public function startEngine(): string {
        return "Engine " . $this->model . " started.";
    }
}

Example of usage:

<?php

$myCar = new Car("Toyota"); // Creating an object
echo $myCar->startEngine(); // Calling the method

Advantages of OOP:

• Modularity: Code is divided into independent blocks (objects), which simplifies understanding and maintenance.
• Code reuse: Thanks to inheritance and objects, code duplication can be avoided.
• Flexibility: Polymorphism allows easy extension of functionality without changing existing code.
• Improved structure: OOP helps organize code logically.