SEO stands for search engine optimization and refers to the process of maximizing website traffic by improving rankings in search engine results. There are two categories of SEO: on-page SEO and off-page SEO. On-page SEO involves optimizing individual page elements like titles, descriptions, URL structures and body text, while off-page SEO focuses on outreach activities to build backlinks, like creating shareable content, engaging on social media, and contributing as a guest author. The goal of both on-page and off-page optimization is to help search engines understand what the website content is about and determine its relevance to specific search queries.