Hi, when you are using OOP (object oriented programming), you describe objects instead of functions or task, when you talk about an common object, let's said a car, the car is a Class an it have properties like:
Color
Number of seats
Model
Brand
number of km
etc.
the properties can be for read an write, in my experience is the same get=read, set= write, you can protect the access of a property only to be written by some method instead allowing the end user to write this property.
Best regards.