The ballpoint pen is a writing instrument that uses dry thick ink and relies on the freely rotating steel ball on the pen head to be transferred to the paper. It has the advantages of simple structure, convenient carrying, writing lubrication, and suitable for rewriting. A ballpoint pen is a pen that uses tiny rotating beads made of brass, steel or tungsten carbide that releases ink onto the paper as it is being written. The ballpoint pen is very different from its predecessors, the reed pen, the feather pen, the metal pen tip and the fountain pen. The writing principle of the ballpoint pen mainly uses the ball to directly contact the paper surface during writing to generate friction, so that the ball rolls in the ball seat and brings out the ink or ink in the pen core to achieve the purpose of writing.