Following are the benefits of using hidden frames:
1.You can cache more than one data field.
2.The ability to cache and access data items stored in different hidden forms.
3. The ability to access JScript® variable values stored in different frames if they
come from the same site.
The limitations of using hidden frames are:
1. Hidden frames are not supported on all browsers.
2. Hidden frames data and be tampered thus creating security hole.