Question about Sessions vs' Cookies



What I am going to play around with and make is a shopping cart app. I was debating using cookies or sessions to store their current items. I know sessions are more secure then cookies, but is there any other immediate advantages to using sessions over cookies? I imagine since they are stored on the server, access to them may be a bit quicker. *shrugs*

Also, is using sessions sound like a good idea for storing the shopping cart info that the user selects? I haven't made a cart app yet, so I was just wondering if sessions is the way to go.
I'd agree that sessions are a better bet than cookies for data that changes rapidly. They can be more secure too. Many of the programmers I know also store backup session data within the db which can be very helpful, 'specially if you have to port values between servers.
also when using sessions the only cookie that is put onto the client side is the session id all other information resides on the server. Not only making it more secure but easier to work with.
Another good reason to use sessions is the fact that the user could have the cookies option disabled.