Cookies are small text files stored in browser memory that help websites function. Some are essential, acting as a site’s short term memory so that user selections and logins persist when navigating between pages. Others support non-essential functions like personalized ads. Users must opt-in to non-essential cookies. While cookies are generally ephemeral, some are more durable. Session-based cookies are only retained while the browser session remains active. Persistent cookies are not bound to a browser session. If used, their duration and function must be disclosed.