What is the Difference Between Similar But Different Things, Terms, and Objects

What is the Difference between Paracetamol Motrin Aleve Tylenol and Advil

There are many medicines which we commonly used in our daily lives. Usually, they are pain killers, as we need them for common muscular pains, body pains and headaches. They all are different in composition, but usually we use them for the same purpose.