.ST45 File Extension

Project file created by the trial version of SuperCard, a high-level visual development tool; stores a data document, which includes user interface components, program resources, and the logic that drives the interface; enables users to save projects while evaluating the software.

The full version of SuperCard uses the .SC45 extension, which stands for "SuperCard 4.5," the version that first used the SC45 and ST45 extensions. Subsequent versions of the software still use these file extensions.