Web storage

Data created by individuals or businesses must be stored so that it is easily accessible for further processing.

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

Web cookies can improve data accuracy

A cookie is a piece of information that is stored by web browser in the user’s; computer, where it waits to be sent back to the server the next time the browser accesses that particular web address.

A cookie is just a simple text file that usually contains a website address and a unique ID.

By returning a cookie to a web server, the browser provides the server a means of associating the current page view with prior page views in order to ‘remember’ something about the previous page request and events.

An e-commerce site might use a cookie to store information about the purchases a user has made in the past.

When the user returns to the site, the site’s software can retrieve the cookie-based data and use the data to create a custom page that contains products similar to those the user has purchased in the past.

Cookie comes in two minor variations: session cookies and persistent cookies.

Session cookies last only as long as the visitor in the site and are deleted after the user closes her web browser or after some period of inactivity.

Persistent cookies last beyond a single visit and have an expiration date sometime in the future.

Cookies are extremely limited in size. Generally, only about 4kb of data can be set in a cookie, meaning they are unacceptable for large values such as documents or mail.

Cookies provide a great service to web measurement application, allowing unique visitors to be tracked from visit to visit and enabling valuable measurements like frequency of visit and lifetime value.
Web cookies can improve data accuracy