SEO (Search Engine Optimization)  SEO typically refers to organic search engine optimization, meaning a site isn't paying for placement through Paid Search. Also see Organic Search Results. SERP (Search Engine Result Page)  The page of listings returned by a search engine when one performs a query.

SEO means Search Engine Optimization and is the process used to optimize a website's technical configuration, content relevance and link popularity so its pages can become easily findable, more relevant and popular towards user search queries, and as a consequence, search engines rank them better.