SEO (Search Engine Optimization) is a critical practice for improving a website's visibility on search engines like Google. It involves optimizing both on-page and off-page elements to enhance rankings. On-page SEO includes factors like keyword usage, content quality, meta descriptions, and mobile-friendliness. Off-page SEO focuses on building backlinks and social media engagement to boost site credibility. Technical SEO ensures the website is easy for search engines to crawl and index, including aspects like page speed and structured data. Effective SEO helps drive organic traffic, increase online presence, and ultimately improve conversion rates for businesses.