This document provides an overview of digital marketing. It defines digital marketing as using online activities to build customer relationships and generate sales. It discusses why people are going online more and the benefits of digital marketing like convenience and measurability. The key components of digital marketing are explained as search engine optimization, pay per click advertising, social media marketing, and more. Search engine optimization aims to optimize websites to rank higher organically in search engines while pay per click involves bidding on keywords and paying when users click ads. Social media marketing can increase brand awareness at low cost and enable campaigns to go viral. Measurement of digital marketing return on investment is also covered.