This document provides an introduction to search engine optimization (SEO). It explains that SEO is the process of improving websites to rank higher in search engines for targeted keywords. On-page optimization focuses on technical elements like HTML tags, website structure and script usage. Off-page optimization involves other techniques like link building, email marketing and advertising. Key ranking factors for search engines include internal link structure, link popularity and relevance, crawlability, and content relevance. Popular SEO tools are also mentioned that provide features like ranking monitoring, backlink management, and search engine data analysis to optimize websites.