A 60-bit word is typically used for high-precision floating-point calculations; it can also store 10 6-bit characters.James L. Peterson, Computer Organization and Assembly Language Programming, 2014, , p. 46
Examples The only widely-used computers with 60-bit words were produced by Control Data Corporation (CDC),Peterson; Concise Encyclopedia of Computer Science, 2004 ; Linda Null, Julia Lobur, Essentials of Computer Organization and Architecture, 2014, ; John Y. Hsu, Computer Architecture: Software Aspects, Coding, and Hardware, 2017, including the CDC 6000 series, the CDC 7600, and the CDC Cyber 70 and 170 series. Though the addressable unit was the 60-bit word, instructions were either 15 or 30 bits.
Early design documents for the IBM 7030 Stretch tentatively specified its word length as 60 bits; the final design used 64.Werner Buchholz, "Memory Word Length", STRETCH Memo no. 40, July 31, 1956, archived at the Computer History Museum
Emulator Museum examples of 60-bit CDC machines exist. There also exists an emulator for the series which will simulate the CDC 60-bit machines on commodity hardware and operating systems.
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