This presentation provides an overview of pesticides. It defines pesticides as substances intended to prevent, destroy or lessen damage from pests like insects, plants or other organisms. It then classifies and gives examples of different types of pesticides like herbicides, insecticides, fungicides. The presentation discusses the chemical composition and working mechanisms of common synthetic pesticides. It outlines both the benefits of pesticides for crop protection and public health, as well as their environmental and health hazards. The Bhopal gas tragedy is presented as an example of a major pesticide accident. Finally, the presentation introduces alternative approaches to pesticides like integrated pest management and biological control using natural predators, parasites or pathogens.