The suanpan is an abacus of Chinese origin first described in a 190 CE book of the Eastern Han Dynasty, namely Supplementary Notes on the Art of Figures written by Xu Yue. However, the exact design of this suanpan is not known.
There are two types of beads on the suanpan, those in the lower deck, below the separator beam, and those in the upper deck above it. The ones in the lower deck are sometimes called earth beads or water beads, and carry a value of 1 in their column. The ones in the upper deck are sometimes called heaven beads and carry a value of 5 in their column.
The similarity between the Roman abacus to the Chinese one suggests that one must have inspired the other, as there is strong evidence of a trade relationship between the Roman Empire and China. However, no direct connection can be demonstrated, and the similarity of the Abacus could be coincidental, both ultimately arising from counting with five fingers per hand.
Up until 2002 or so, accountants and financial personnel in mainland China had to pass certain graded examinations in bead arithmetic before they were qualified.
I picked up this gorgeous Chinese Suanpan in an old garage on a country road outside Kuching Borneo.
It was laying on a pile of old newspapers covered in dust and I asked this wizened old guy in my atrocious Malay if he still used it.
He looked up from his desk with a mouth of stained, broken and missing teeth and laughed.
He then pulled out his iPhone and turned on the calculator!