Kelly Guimont for TUAW:

Twenty-five years ago today, HyperCard was released at Macworld Expo Boston. Apple’s software construction kit for the rest of us began shipping on every new Mac as of August 11, 1987; you could also buy it for $49. It required 1 MB of memory (yes, one megabyte) and a pair of 800K floppy drives, or one floppy drive + a hard disk. (Announced at the same time: the ImageWriter LQ, the Apple Fax Modem, and MultiFinder.) Times have indeed changed.

HyperCard inspired a generation of Mac users to think about how they could interact with their machines in ways they never could before – creating their own stacks to do everything from keep track of recipes to business applications to games (Myst, famously, started as a HyperCard stack).