Internal search (SEO)
Internal search is the built-in search engine on an e-commerce or editorial site. Its result URLs must be excluded from crawling (noindex or robots.txt) to prevent the generation of thousands of empty, non-indexable pages that waste crawl budget and dilute site quality.
In practice
Internal search logs are an untapped SEO resource: they reveal the terms visitors look for on your site but cannot find. An auto parts distributor discovered that 'Peugeot 308 1.6 HDi head gasket' generated 120 internal searches per month with no dedicated page — creating the matching category page captured immediate traffic from organic search.