The abacus is a counting device that has not only been used for thousands of years throughout mathematic history, but is still used today. Its eventual portability allowed it to be introduced to all parts of the world. The abacus evolved into a tool that could be used across cultures. Its design allows addition, subtraction, multiplication, and division to be done efficiently without pencil and paper, as accurately as the hand held calculator. The abacus although often still thought of as an ancient device, still allows users to process operations in the same manner that it has been done for thousands of years. Moreover, the abacus provides students in today’s classrooms with a visual sense of numbers and a more hands-on manner of learning arithmetic.  
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References

CMA Mental Arithmetic International Olympiad 2016. (2016). CMA Singapore. Retrieved April 2018, from https://www.youtube.com/watch?v=HKphPZ9YmUc