A Class, in Programming Languages, are a user-defined data type, which holds its own data members and member functions, which can be accessed and used by creating an instance of that class. A class is like a blueprint for an object.
For Example: Consider the Class of Cars. There may be many cars with different names and brands but all of them will share some common properties like all of them will have 4 wheels, Speed Limit, Mileage range, etc. So here, Car is the class, and wheels, speed limits, mileage are their properties.
A Class is a user-defined data type that has data members and member functions. Data members are the data variables and member functions are the functions used to manipulate these variables, and together these data members and member functions define the properties and behavior of the objects in a Class.
In the above example of class Car, the data member will be speed limit, mileage, etc. and member functions can apply brakes, increase speed, etc. An Object is an instance of a Class. When a class is defined, no memory is allocated but when it is instantiated (i.e. an object is created) memory is allocated.