The library is a convenient alternative to sharing a root domain cookie. Unlike cookies, your client-side data isn't limited to a few kilobytes - you get up to 2.49M chars. For a client-heavy application, you can potentially shave a few KB off your request headers by avoiding cookies. This is all thanks to LocalStorage, which is available in IE 8+, FF 3.5+, Chrome 4+, as well as a majority of mobi
