This document provides an overview of key concepts in advertising. It defines advertising and its purposes, which include selling products and services. Advertising reaches large audiences through mass media channels. Effective ads attract attention, build interest and desire, and inspire action. Advertisers develop strategies to identify unique brand attributes and messaging. A variety of techniques can be used to create rational, emotional, social, or biologically-focused ads. The roles of advertisers, agencies, media, suppliers, audiences and new technologies are also discussed.