The Famicom Disk system
(ファミリーコンピュータ ディスクシステム)
The Family Computer Disk System, sometimes shortened as the Famicom Disk System or simply the Disk System, and abbreviated as the FDS or FCD, is a peripheral for Nintendo's Family Computer home
video game console, released in Japan on February 21, 1986. It uses proprietary floppy disks called "Disk Cards" for data storage. It was announced, but not released, for the Nintendo
Entertainment System in North America and the PAL region. Through its entire production span, 1986–2003, 4.44 million units were sold.
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Source: Wikipedia
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