Security
Userpicwhy do we need cookies
Posted by Moxietype

If Oreo or Girl Scouts' cookies come to your mind, it means that you have to read this little explanation why we need them.

Technically, cookies are arbitrary pieces of data chosen by the Web server and sent to the browser. The browser returns them unchanged to the server, introducing a state (memory of previous events) into otherwise stateless HTTP transactions. Without cookies, each retrieval of a Web page or component of a Web page is an isolated event, mostly unrelated to all other views of the pages of the same site.

Source: Wikipedia

It is absolutely necessary to use the cookie in order for a Web server to identify the user as a legitimate logged-in user in a recorded PHP session. Same way when you go to do your online banking or shopping at Amazon.com