- A very old type of calculator, which uses beads on a rod to count. The abacus is one of the oldest types of counting system ever.
Who invented the abacus?Edit
There have been many different variations on abacuses for thousands of years, but the modern day abacus comes from China, in around 1600 AD.
The original abacus was actually just a board of sand which people could write numbers and calculations on. This shows the importance of Etymology: the word "abacus" only became used in the context of counting frame as recently as the 17th Century.