Picture a car dealership. There are many different types of vehicles for sale. The salespeople know every detail about every one. But the accountants inside only care that a vehicle is getting sold. Model this system:

The dealer sells Hatchbacks and Sedans

These both inherit from Vehicle, and Vehicle cannot have properties. It can have methods, virtual methods, or pure virtual methods.

Every vehicle has a price

Hatchbacks have 5 doors and sedans have 4

Every vehicle has a trunk. A hatchback holds 30 cu ft, a sedan 20

Lastly, every vehicle can be started

Make two functions that take a Vehicle pointer as an argument*. Call one Salesperson and the other Accountant.

void Salesperson(Vehicle* tWhat);

void Accountant(Vehicle* tWhat);

The salesperson function:

Prints the type of car

Prints how many doors it has

Prints the trunk size

Starts the car

The Accountant function:

Prints the price

If these functions were in a class, they'd be methods. No Sales or Accountant classes.