HyperMedia software developed by BillAtkinson? and many others in the late 1980s for the MacOs (System 6, around when the Mac II and Mac SE came out). They basically integrated a paint program (BillAtkinson? also developed MacPaint?), some sound tools, and a programming language into a HyperText system based on "cards".
These cards took over the screen (unless you had a Mac with a big screen, which at that time meant the Macintosh II), and in any case you couldn't have more than one "card" open at once. Documents are called "stacks" (as in a stack of cards).
In general its combination of abilities works. Many NonProgrammers? have gone from drawing pictures to learning to make buttons to link around, to eventually taking the plunge and learning and using the built-in language, HyperTalk? -- for which extensions can, and many have been, written.
Each computer had a default home stack/card (completely modifiable as any card), and settable preferences, including the user's name and other global variables.
AppleCorporation? stopped bundling it with the MacOs long ago (breaking a promise to Bill), and has barely paid any attention to it in ages (color and multiple windows have been added). Never developed for UnixOs?, MsDos? or MsWindows?, although SuperCard?, in many ways a more able product, does MsWindows?.
Who wrote it? -- SunirShah