What is the purpose of the self parameter in a method?

The 'self' parameter in a method is a reference to the instance of the class on which the method is called. It is used to access attributes and methods of that particular instance.

When an instance attribute is created, it is specific to that instance of the class. To access these attributes in a method, we need to use the 'self' parameter. It allows us to reference that specific instance's attributes. Example: Consider this Python code where we use 'self' to access instance attributes. ```python class Person: def __init__(self, name, age): self.name = name self.age = age def display(self): print(f"Name: {self.name}, Age: {self.age}") person1 = Person("John", 30) person1.display() ```

In addition to accessing instance attributes, the 'self' parameter is also used to invoke other methods within the same class on the same instance. Example: Consider this Python code where we use 'self' to access another instance method. ```python class Vehicle: def __init__(self, brand, model): self.brand = brand self.model = model def start_engine(self): self.engine_status = "Running" print("Engine started.") def stop_engine(self): self.engine_status = "Stopped" print("Engine stopped.") def drive(self): self.start_engine() print(f"Driving {self.brand} {self.model}") self.stop_engine() car = Vehicle("Toyota", "Corolla") car.drive() ```

The 'self' parameter is mandatory in Python class methods because it provides a way to reference the specific instance of an object that the method is called on. Without 'self', there would be no way to distinguish which instance's attributes and methods should be accessed, leading to conflicts or errors. Although Python uses the 'self' parameter, other languages like Java or C++ have keywords such as 'this' to achieve the same purpose.