Differences between cookies and sessions

Hi there,
I want to learn the differences between sessions and cookies in PHP.Please help me.
Please let me know if there any video demonstrations that explain sessions and cookies.
Thanks in advance.

Cookies and server side sessions are related in that they are both ways to persist data. This is required because of the fact that http is a stateless protocol, meaning that each request and response are independent transactions. Cookies are stored on the client. You might use them to store the contents of a shopping cart, or a user login id for a particular site. Or you could store a setting so that the user is automatically logged in, similar to what occurs here in the adobe site / forums. You can set various options for when cookies expire. Cookies that persist when the browser is closed are store in files, otherwise they could be store in memory only. Cookies can be created using either client or server side code.
Server side sessions are created on the server with a server side scripting language. A session id is generated and stored as a token on the client (in an in memory cookie) so that the server can track requests from the same originating client. Session variables are ways to store data related to the session on the server. Sessions use server resources which is why you should only use them when necessary and destroy them when done. When the session is destroyed, the session variables are gone so if you want to keep them for later you can store them in a database or store them in a cookie.
HTTP cookie - Wikipedia, the free encyclopedia
Hope that helps

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    Regards

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