You can set up your website so that users can log into it that is, so that the site supports membership. This can be useful for many reasons. For example, your site might have pages that should be available only to members. In some cases, you might require users to log in in order to send you feedback or leave a comment such as facebook, twitter, blogger or any other websites which needs identification of the user.
Flipkart, Amazon not needs identification to add products to the cart, but when you want to place an order they needs an identification. So at that time Membership is needful for user identification.
You can learn more about Membership in ASP.NET on below links of MSDN Library :
Learn about role provider for registered members :
Hope this will help you.
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