SalesCart uses a totally new and re-designed base architecture for the checkout pages and checkout portion of SalesCart. This new architecture uses the latest and greatest version of the VBScript libraries that support classes and XML.
See Also
How SalesCart PRO differs from SalesCart STD
SalesCart-PRO -Designed with the "Professional" Web Developer in Mind
Wizard-Driven Start-Up
Features in SalesCart PRO
Features Common to SalesCart STD