Pagination in SEO refers to how multi-page content — article series, category listings, product grids — is handled so that search engines index the correct pages and consolidate signals appropriately. Google supported rel=prev and rel=next link attributes for years to signal paginated series, but officially deprecated them in 2019, having already stopped using them in practice. Current best practice is to ensure that the first page of a paginated series is the strongest, most link-worthy page; to use a rel=canonical self-referencing tag on each page rather than pointing all pages to page one (which would make them invisible to crawlers); and to consider infinite scroll implementations carefully, using History API pushState to generate crawlable URLs. Key pages in a paginated set should remain within a reasonable crawl depth from the site root.