Glossary term
What is Origin? Meaning for developers
Scheme + host + port together (for example https://site.com:443). Two URLs are the same origin only if all three match.
Learn it properly · The Browser ContractLesson 4: CORS Explained: Same-Origin Policy, Preflights and CredentialsWhy CORS protects the browser and is not a firewall for the server, what makes a preflight request, and why you cannot use a wildcard origin together with credentials.