For years, cookies were the only option available to most web developers for storing temporary information.
Using cookie, a developer could store up to 4KB of data. The web storage system can handle electronic forms similar to the forms available in Outlook.
Instead of Outlook forms, HTML – or ASP-based forms are launched when the user opens an item in a Web browser. HTML expands beyond the storage capabilities that cookies provide to allow session- based storage and long-term storage.
Web storage is a great complement to Offline Applications, because the user need somewhere to store al the user data while he or she working offline, web storage provide it.
There are two kinds of HTML web storage: session storage and local storage.
In local storage, data is saved even after the window is closed and is available to all windows that are loaded from the same origin.
Session storage is per-page-per-window and is limited to the lifetime of the window. Data is stored with the window object.
They are very similar to cookies in that they allow the user to use JavaScript to set name, value pairs that the user can retrieve across multiple page reloads.
Web storage
