What does Price per person per night based on double occupancy mean?

Here is an example: If the price is $50 per person, per night, based on double occupancy, it means that the room is meant for 2 people, and that each person will pay $50, therefore the total cost for the room sleeping 2 people, is $100.

Usually, single occupancy is almost double the per person cost of double occupancy: The same room that cost 2 people $100 will cost 1 person $100.

The principle is for the hotel to sell the room at a minimum cost, therefore, 2 people stay cheaper than 1.