How Do Classes Work and How Do They Differ From Objects?

In Python, classes and objects work hand in hand to organize and manage data. You build a class to define shared behavior, then create objects that use those behaviors. In other words, a class is like a blueprint or template you use to create objects with. Let's look at what classes are, and how to use them to create objects. To create a class, you use the `class` keyword followed by the name of the class and a colon. Then within the class, you can add an initializer, along with any attributes and methods. Attributes are like variables within a class, and are used to store data. Methods are functions defined within a class, and are the actions objects created with a class can perform. Here's the basic syntax of a class: ```python class ClassName: def __init__(self, name, age): self.name = name self.age = age def sample_method(self): print(self.name.upper()) ``` * `class ClassName` is made up of the `class` keyword to create a class, followed by the name of the class, here called `ClassName`. It is common in Python to use the **PascalCase** convention when naming classes. * `def __init__(self, name, age)` is the special method automatically called when a new object is created. It initializes the attributes of the objects that will be created with the class. In addition to that, the first parameter of `__init__` is always a reference to the specific object being created or used. By convention, this parameter is named `self`, but technically, you can use any name. `self` lets you access the object's own attributes and methods. * `self.name = name` and `self.age = age` are the attributes the objects will have. * `def sample_method(self):` is the method each object created can call. * `print(self.name.upper())` is what the `sample_method` method will do, in this case, it prints the name in uppercase. If that all sounds like a lot, don't worry. Let's take a look at a similar example of a `Dog` class, and how you can create objects from that: ```python class Dog: def __init__(self, name, age): self.name = name self.age = age def bark(self): print(f"{self.name.upper()} says woof woof!") ``` With this `Dog` class, you can create an object. Here's the basic syntax for creating objects from a class: ```python object_1 = ClassName(attribute_1, attribute_2) object_2 = ClassName(attribute_1, attribute_2) ``` You can also call any of the methods defined in the class from each object: ```python object_1.method_name() object_2.method_name() ``` Now let's create two dogs by using the `Dog` class as the blueprint: ```python class Dog: def __init__(self, name, age): self.name = name self.age = age def bark(self): print(f"{self.name.upper()} says woof woof! I'm {self.age} years old!") dog_1 = Dog("Jack", 3) dog_2 = Dog("Thatcher", 5) # Call the bark method dog_1.bark() # JACK says woof woof! I'm 3 years old! dog_2.bark() # THATCHER says woof woof! I'm 5 years old! ``` As you can see, we create two dog objects using the `Dog` class. When initializing `dog_1`, the string `Jack` and the number `3` are passed, which sets the `name` and `age` attributes for that instance. And `dog_2` is initialized with the string `Thatcher` and number `5` as its `name` and `age`, respectively. Then when you call the `.bark()` method on `dog_1` and `dog_2`, you can see how both outputs differ, and use the unique `name` and `age` attributes you passed in when creating each object. In summary, the difference between a class and an object is that a class is the template or the blueprint, and an object is what is created using that template. Also, a class defines what data and behavior the object should have, and an object holds the actual data and uses that behavior. You write a class once, and you can make many objects from it, each with different data.