The rel="______" attribute value is often used alongside target="_blank" to enhance security.

The rel="noopener" attribute is used to ensure that when a new window or tab is opened via target="_blank", the new page runs in a separate process and doesn't have access to the source window via the window.opener property. This helps prevent potential malicious attacks. rel="noreferrer" also provides this feature but with the added behavior of not sending a referrer header.