Object (computer science) facts for kids
In Object-oriented programming, an object is like a special digital "thing" or "building block" that programmers use when they create computer programs. Imagine you're building with Lego bricks. Each Lego brick is like an object.
An object holds two main things:
- Data: This is information about the object. For example, if you have an object for a video game character, its data might include its name, health points, or score.
- Methods: These are actions or things the object can do. For the game character, methods might be `jump()`, `attack()`, or `collectCoin()`.
Think of it like this: the data inside an object is usually hidden away, like the secret ingredients in a special recipe. You can't just reach in and change them directly. Instead, you use the object's methods (its actions) to interact with that data. This is called an interface. The interface is like a set of buttons or controls that let you use the object without needing to know all its inner workings.
How Objects Work: A Bank Account Example
Let's imagine a bank account as an object in a program.
This bank account object would have:
- Data:
- Your current money balance.
- A history of all the money you've put in or taken out.
- Methods (actions you can do):
- `deposit()`: To put money into the account.
- `withdraw()`: To take money out of the account.
- `checkBalance()`: To see how much money you have.
When you want to use your bank account in a program, you don't directly change the balance. Instead, you use the `deposit()` or `withdraw()` methods. These methods are smart! For example, the `withdraw()` method would check if you have enough money before letting you take it out. If the bank allows you to borrow money (a "credit limit"), the method would also check that you don't go over that limit.
A bank manager might have different actions they can do with the account object, like setting the maximum amount you can withdraw or changing fees. This shows how different people (or parts of a program) can interact with the same object in different ways, depending on their role.
Objects of the Same Type
An object is always created from something called a class. You can think of a class as a blueprint or a cookie cutter. The object is like the actual cookie you make from that cutter.
For example, if you have a "Car" class (the blueprint), you can create many different car objects from it:
- A red sports car object.
- A blue family car object.
- A yellow taxi car object.
All these car objects are made from the same "Car" blueprint, so they all have things like a color, a speed, and methods like `drive()` or `brake()`. But each specific car object will have its own unique color and speed.
It's easy to compare two objects made from the same class, like comparing a red apple to a green apple. They are both apples, but they have different colors and sizes. However, it's much harder to compare an apple object to a wrench object, because they are completely different kinds of things!
Related pages
See also
In Spanish: Objeto (programación) para niños
