The database where search engines store information about web pages. Getting indexed is necessary to appear in search results.
The index is the database where search engines store and organise pages they’ve crawled. If a page isn’t indexed, it can’t appear in search results. Indexing depends on crawl access, content quality, canonical signals, and whether the page is worth storing (unique, useful, and not blocked by directives).
robots.txt or a noindex directiveBrowse related definitions in the same glossary category.
Algorithm
A complex system used by search engines to retrieve data and deliver results for a query. Google uses multiple algorithms to rank websites.
Algorithm Update
Changes made to a search engine's ranking algorithms that can impact website visibility and traffic.
AMP (Accelerated Mobile Pages)
A framework that enables ultra-fast loading of mobile pages by simplifying HTML and limiting scripts.
API Quotas
Hard limits on total API usage over a billing period, often tied to pricing tiers.
API Rate Limits
Restrictions on how many API requests can be made within a time period, requiring throttling and retry logic.
Broken Link
A hyperlink that no longer works because the destination page has been deleted or moved. Damages UX and SEO value.
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