Cross-Origin Resource Sharing (CORS) is a mechanism that uses additional HTTP headers to tell browsers to give a web application running at one origin, access to selected resources from a different origin. A web application executes a cross-origin HTTP request when it requests a resource that has a different origin (domain, protocol, or port) from its own. An example of a cross-origin request: the
![Cross-Origin Resource Sharing (CORS) - HTTP | MDN](https://cdn-ak-scissors.b.st-hatena.com/image/square/e51bd6dc33a667d35eb4146698a198e55ff92d6e/height=288;version=1;width=512/https%3A%2F%2Fdeveloper.mozilla.org%2Fstatic%2Fimg%2Fopengraph-logo.72382e605ce3.png)