A ballpoint pen (Philippine English: ballpen, British English: biro) is a writing instrument, with an internal ink reservoir and a sphere for a point. The internal chamber is filled with a viscous ink that is dispensed at its tip during use by the rolling action of a small sphere. The sphere, usually from 0.5 mm to 1.2 mm in diameter, may be made of brass, steel, tungsten carbide, or any durable, hard (nondeformable) material.
Read more about Ballpoint Pen: History, Description, As Art Medium, Standards
Famous quotes containing the word pen:
“If you tie a horse to a stake, do you expect he will grow fat? If you pen an Indian up on a small spot of earth, and compel him to stay there, he will not be contented, nor will he grow and prosper. I have asked some of the great white chiefs where they get their authority to say to the Indian that he shall stay in one place, while he sees white men going where they please. They can not tell me.”
—Chief Joseph (c. 1840–1904)