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Gridlode
Glossary

What is Certificate Transparency?

Public, append-only logs of every certificate issued by public authorities.

Because every certificate is logged, CT logs reveal subdomains that ever had a certificate, a common way to map a company's internet footprint.

Related terms

  • SSL/TLS certificate: A certificate that proves a site's identity and enables HTTPS encryption.
  • robots.txt: A file at the root of a site telling crawlers which paths they may fetch.
  • llms.txt: A Markdown file at /llms.txt that gives AI assistants a curated map of a site.