Every project involves a number of players.
In all applications built by BigBinary you will find
Oliver is the owner of the product BigBinary is building.
In another words Oliver is the customer of BigBinary.
The customer of Oliver is
For example let's say that BigBinary is built a Quiz application. Oliver will be the customer of this Quiz application. It means Oliver will create quizzes. Now Oliver wants someone to take these quizzes. May be Oliver is a teacher and his students will be taking the quiz. We need a person who will be taking the quiz. That would be Eve. In another words Eve is the customer of Oliver.