In this lesson we are going to go over the Cahn-Ingold-Prelog priority rules and their applications towards different types of compounds. In a typical introductory organic chemistry course, we look at the R/S and E/Z stereodescriptors that are based on the CIP rules. We use the R/S stereodescriptors for the chiral atoms. While the E/Z system describes the stereochemistry of double bonds.