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10.5 Summary

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Both sessions and cookies are useful ways of storing data across web pages, and have their own advantages: sessions are more secure, and cookies can survive even after the user closes their browser.
You can rewrite the session system with PHP so that your session data is stored wherever you want - perfect for large, distributed server farms.
Unless you are using output buffering, cookies need to be sent before the main body of your page in order to comply with the HTTP protocol.
To store complex data types such as arrays and objects in a cookie or session you can serialize() to explicitly make them a string first.

<< 10.4 Storing complex data types		10.6 Exercises >>
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A PHP User - 29 Aug 2008

I wouldn't suggest putting the username in a cookie, and ONLY looking for the cookie, because they could always change the cookie to something else if you don't make sure that they're who they say they are!

singpolyma AT gmail.com - 29 Aug 2008

One thing I would like to note is that there is a way to have the permanece of cookies with the security of sessions. What you do is you store a unique ID (or if you have a login, a username) in a long-lasting cookie youself. Then you store their data in a database and reference it manually using the cookie. This is what I use for user account data on my websites and it works very well.

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