It is insecure to allow a webpage to request any resources from any other {{glossary("domain","domains")}} without limitation. CORS (Cross-Origin Resource Sharing) is a system that determines whether to block or fulfill these requests.
<p>It is insecure to allow a webpage to request any resources from any other {{glossary("domain","domains")}} without limitation. <strong>CORS </strong>(Cross-Origin Resource Sharing) is a system that determines whether to block or fulfill these requests.</p>
<h2 id="Learn_more">Learn more</h2>
<h3 id="General_knowledge">General knowledge</h3>
<ul>
<li><a href="/en-US/docs/Web/HTTP/Access_control_CORS">HTTP access control (CORS)</a> on MDN</li>
<li>{{Interwiki("wikipedia", "Cross-origin resource sharing")}} on Wikipedia</li>
</ul>
<h3 id="Technical_reference">Technical reference</h3>
<ul>
<li><a href="https://www.w3.org/TR/cors/">Specification</a> on W3C recommandation</li>
</ul>