You can think of localStorage
as cookies on steroids. If you've used cookies, you are not new to persistent data on the web. You get persistent browser-based (and browser-limited) string-based key value storage, more storage* and you lose the straight-forward ability for cross-subdomain storage (you can accomplish that goal in this manner). It will not sync with your server automatically, it will not even sync with other browsers on the same machine without some external process. The localStorage
programming concepts will (mostly*) work the same on any browser that supports the W3C localStorage
spec
I tested it in one machine and 3 different browsers
3 different browsers as in Chrome, Firefox and IE or 3 different tabs/windows of the same browser? I ask because localStorage does not synchronize between browsers (unless you have some external process performing the synchronization).
Hope this helps
* different browsers have different levels of storage they allow, this answer explains more