Point Of Sale

This can mean a retail shop, a checkout counter in a shop, or a variable location where a transaction occurs in this type of environment. Additionally, Point Of Sale sometimes refers to the electronic cash register system being used in an establishment. Point Of Sale systems are used in restaurants, hotels, stadiums, casinos, as well as retail environments — in short, if something can be sold, it can be sold where a Point Of Sale system is in use.

Source: Wikipedia