SEO, or search engine optimization, is the process of enhancing a website's visibility and ranking in search engine results through various techniques such as on-page, off-page, and technical optimization. On-page SEO involves optimizing individual web pages for better traffic, while off-page SEO focuses on techniques to build authority outside the website, such as link building and social media marketing. Technical SEO ensures the website's underlying technical elements enhance crawlability and performance, contributing to overall search engine success.