This document provides an introduction to search engine optimization (SEO) including definitions, key factors to consider, and best practices. It explains that SEO involves strategic and practical activities to maximize how content ranks in search engines and attracts organic traffic. Important elements include developing a strategy, building a high-quality website with optimized on-site content and off-site links. The document outlines technical SEO considerations and emphasizes creating valuable content targeted at real users. It also warns against poor practices like over-optimization, link schemes, and experiences that hurt users.