How to store information about the client device without using cookies in JavaScript


I am building a little HTML program (well, not little), but I have got options that I would like to permanently write to the client's machine without using cookies. reason being is cookies will expire, and have a storage limit of 4 KB. how would I do that without jquery.

Client side cookies can be deleted any time. Server side cookies cannot be deleted and the expiration date can be set. You can't write to a machine from an HTML page though, it's not allowable by any means. It would have to be a hack and a virus if such a violation would occur.