This document provides an introduction to green chemistry. It defines green chemistry as the design of chemical products and processes that reduce or eliminate the use of hazardous substances. The history and key principles of green chemistry are discussed. The 12 principles developed by Paul Anastas and John Warner cover concepts like pollution prevention and the use of safer, environmentally benign substances and energy efficient processes. The importance of green chemistry is to prevent waste, design safer chemicals and products, and support a transition to sustainable agriculture.