Everything is an object
An object is a fundamental building block of an object-oriented language. Integers, strings, floating point numbers, even arrays and dictionaries, are all objects. More specifically, any single integer or any single string is an object. The number 12 is an object, the string "hello, world" is an object, a list is an object that can hold other objects, and so on. You've been using objects all along and may not even realize it.
Objects have types
Every object has a type, and that type defines what you can do with the object. For example, the int
type defines what happens when you add something to an int, what happens when you try to convert it to a string, and so on.
Conceptually, if not literally, another word for type is class. When you define a class, you are in essence defining your own type. Just like 12
is an instance of an integer, and "hello world"
is an instance of a string, you can create your own custom type and then create instances of that type. Each instance is an object.
Classes are just custom types
Most programs that go beyond just printing a string on the display need to manage something more than just numbers and strings. For example, you might be writing a program that manipulates pictures, like photoshop. Or, perhaps you're creating a competitor to iTunes and need to manipulate songs and collections of songs. Or maybe you are writing a program to manage recipes.
A single picture, a single song, or a single recipe are each an object of a particular type. The only difference is, instead of your object being a type provided by the language (eg: integers, strings, etc), it is something you define yourself.
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