SEO stands for Search Engine Optimization. It's a set of strategies and practices aimed at improving a website's visibility in search engine results pages (SERPs). The goal of SEO is to increase organic (non-paid) traffic to a website by enhancing its relevance and authority in the eyes of search engines like Google, Bing, and Yahoo. SEO involves various techniques such as keyword research, on-page optimization, content creation, link building, and technical optimizations to improve a website's ranking for specific search queries. Ultimately, effective SEO helps websites attract more targeted visitors and improve their online presence.