算盘(abacus)是中国传统的计算工具，也是中国古代的一项重大发明。阿拉伯数字出现以前，算盘在世界各地广泛使用。算盘是矩形的木框，木框上固定着带算珠的木杆。木框中间的横梁(beam)将木杆分成两部分：木杆上方的两颗算珠 (counting beads)每个代表5,下方的五颗算珠每个代表1。随着算盘的应用，人们总结出很多计算技巧，提高了计算速度。由于算盘易于制造，而且计算口诀易于记忆和操作，因此算盘在中国十分流行。
As a traditional Chinese calculation tool and an important ancient Chinese invention,the abacus was widely used before the invention of Arabic numerals in the world. The abacus is a rectangle with a wooden frame. Within the frame,rods with stringed beads are fixed. The beam in the middle of the frame divides each rod into two parts. The two counting beads in the upper part of each rod represent five and the rest five beads in the lower part represent one. With the application of the abacus, people summarized many calculation tips to help improve the speed of calculation. As the abacus is simple to produce, and its calculation tips are easy to memorize and operate, it is quite popular in China.