...More importantly, however, it's really just a demo. Don't use it for production code without thoroughly reviewing it. Specifically, it lacks secure session ID's and has not been reviewed for XSS, SQL Injection, CSRF...
WARNING #2: This code is written for php3. Most people reading this have probably never even heard of php3. I just tested it out (2015) for fun and found that it doesn't work at all. Please, please; choose not just a different shopping cart, but perhaps a different language. The world has changed since 1998!
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