What is CORS?

Cross-Origin Resource Sharing (CORS) is a security mechanism that allows a web page from one domain (in other words, Origin) to access a resource with a different domain (a cross-domain request).

Same-origin policy (sometimes abbreviated as SOP) is concept in the web application security model, under which, a web browser permits scripts contained in a first web page to access data in a second web page, but only if both web pages have the same origin or domain.

CORS is a relaxation of the same-origin policy implemented in modern browsers.

AWS – Enabling CORS for a REST API resource

MDN – Cross-Origin Resource Sharing (CORS)

Wikipedia – Same Origin Policy