Postcardware

Postcardware, also called just cardware, is a style of software distribution similar to shareware, distributed by the author on the condition that users send the author a postcard.

A variation of cardware, Emailware, uses the same approach but requires the user to send the author an email. Postcardware, like other "novelty" software distribution terms, is often not strictly enforced.

Cardware is similar to beerware.

The concept was first used by Aaron Giles, author of JPEGView. Another well-known piece of postcardware is the roguelike game Ancient Domains of Mystery, whose author collects postcards from around the world. Orbitron is distributed as postcardware. Exifer is a popular application among digital photographers that has been postcardware. Caledos Automatic Wallpaper Changer is a "still alive" project cardware. "Empathy" is a postcardware for password-protected executables. Dual Module Player and Linux were also postcardware for a long time as well. An example for emailware is the videogame Jump 'n Bump.

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