The abacus is composed of frames, beams, racks and beads.

The four sides of the abacus are called frames, also called sides. The horizontal bar in the middle of the abacus is called a beam. The small rod that runs through the crossbeam from the top to the bottom of the abacus is called a gear, also called a "rod". The beads on the abacus are called abacus, also called an abacus. The lower bead near the bottom of the abacus is called the bottom bead, and the upper bead near the top of the abacus is called the top bead.

The origin of the abacus:

The abacus is a traditional Chinese calculation tool. It was invented by the Chinese on the basis of long-term use of arithmetic chips. It is a great and important invention in ancient China. Before the emergence of Arabic numerals, it was a widely used calculation tool around the world.

As for the origin of the abacus, it is said that it can be traced back to the invention of Guan Yu in the late Han Dynasty. It is said that our country had an "abacus" at that time. The ancients strung 10 beads into a group, arranged the groups, put them into the frame, and then quickly moved the beads to perform calculations.

In ancient times, people used small wooden sticks to make calculations. These small wooden sticks were called "shuangchi", and calculations using abacus as a tool were called "shuangsuan". Later, with the development of production, calculations using small wooden sticks were restricted, so people invented a more advanced calculation tool-the abacus.

By the Ming Dynasty, abacus could not only perform addition, subtraction and multiplication operations, but also calculate land area and the size of various shapes.