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Technical Marvels, Part 3: The Yupana – Communications of the ACM

https://cacm.acm.org/blogcacm/technical-marvels-part-3-the-yupana

“The most common bead frames include Chinese, Japanese, and Russian abacuses as well as school abacuses. Less well known is the Roman hand abacus, of which only three original pieces have survived, and the mysterious Incan counting board, the Yupana. The Incas used knotted cords (quipus or khipus)...” (from the page’s text)

In short: Discover the ancient Peruvian abacus, Yupana - a mysterious counting board used by Incas for calculations and possibly urban planning. Learn about its histor... (AI summary)

Topic: News Current Events › Technology News
Quality: Quality 84 scored 12 Aug 2025
Language: english
Text on page: 14,118 characters
Page size: 149 kB
Answered: OK (200), HTML
Last read: 8 Jul 2025
In our index since: 8 Jul 2025
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