Neko is a cat that runs around on the screen, chasing the mouse cursor.

Neko is one of the longest-living software projects, lovingly recreated by the community to run on a wide range of platforms ancient and modern – including PC98, Macintosh, Windows, NEXTSTEP, BeOS, IBM OS/2, Palm OS, iPhone, Android, and Arduino – from personal computers to mobile phones and microcontrollers.

The original software based on this concept, as far as I’ve been able to trace back, was written in the 1980’s by Naoshi Watanabe (若田部 直). It was called NEKO.COM and ran on the Japanese computer NEC PC-9801 in the MS-DOS command line.

The next version ran on the Macintosh computer as a “desktop accessory”. It was called NekoDA, written in 1989 by Kenji Gotoh (後藤寿庵 – also known as Juan Gotoh).

The author, who has since had a career as a manga illustrator, created new image designs for the cat. He has declared them as public domain, and the same pixel art has been used in all following generations.

In 1991, it was ported to Windows 3 by Dara Khani (“Neko Runs Free”) and Michael Bankstahl (“WNEKO”) independently. In 1993, a version was created for the Commodore Amiga.

IBM bundled Neko with OS/2 2.x. Almost all of the user-facing material called it “Cat and Mouse”, but the executable file name was, of course, NEKO.EXE.

In 2010, a programmer neozeed adapted the 32-bit version to build for 64-bit Windows (7/8/10 and so on), ensuring the cat a long life on the popular platform.

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