The abacus was early used for arithmetic tasks. The abacus was initially used for arithmetic tasks. One of the Japanese-made abacus made in China is an aluminum frame plastic bead abacus. The Chinese abacus migrated from China to Korea around 1400 AD. The earliest known written documentation of the Chinese abacus dates to the 2nd century BC. The binary abacus is used to explain how computers manipulate numbers. Some sources mention the use of an abacus called a "nepohualtzintzin" in ancient Aztec culture. This Mesoamerican abacus used a 5-digit base-20 system. It is also called the Soroban system, meaning grading system used in Japanese abacus schools. Above the capital is a square abacus connecting the capital to the entablature. Is what Goldman Sachs did with its Abacus investment vehicle illegal? The bell-shaped lotus beneath the abacus has been omitted. On the ancient abacus and adding board, both addends are destroyed, leaving only the sum. The is an abacus developed in Japan. Furthermore, Regiomontanus could rely on practices with remainder tables from the abacus tradition.