This document provides an overview of search engine optimization (SEO). It defines what a search engine is and how they work by using spiders to index webpages and rank them in search results. It explains that SEO aims to improve a website's natural or organic rankings in search engines through on-page and off-page optimization techniques. The SEO process involves evaluating a website, researching keywords, developing meta tags and content, implementing a linking strategy, and using tools while avoiding black hat techniques. Social bookmarking and pay-per-click (PPC) advertising are also discussed in relation to SEO.