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Decker is a multimedia platform for creating and sharing interactive documents, with sound, images, hypertext, and scripted behavior.

Decker builds on the legacy of HyperCard and the visual aesthetic of classic MacOS. It retains the simplicity and ease of learning that HyperCard provided, while adding many subtle and overt quality-of-life improvements, like deep undo history, support for scroll wheels and touchscreens, more modern keyboard navigation, and bulk editing operations.