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

What is the Difference between Penicillin Augmentin Clarithromycin Amoxicillin

The medical science has progressed very much and the diseases which were thought to be a incurable and were considered as the other name of death. Once malaria was thought to be an incurable disease and it produce havoc on the planet earth. Nobody knew the reason of it and thus is suffering from it alike.