A mechanical pencil, also clutch pencil, is a pencil with a replaceable and mechanically extendable solid pigment core called a "lead" //. The lead, often made of graphite, is not bonded to the outer casing, and can be mechanically extended as its point is worn away as it is being used.
Other names include: microtip pencil, automatic pencil, drafting pencil, technical pencil, click pencil (generally refers to a specific brand), pump pencil, leadholder, pacer (Australian English, ca. the 1980s), propelling pencil (British and Australian English, often refers to higher-end mechanical pencils), pen pencil (Indian English), and lead pencil (Bangladeshi and American English).
Mechanical pencils are used to provide lines of constant width, without need of sharpening, for tasks such as technical drawing as well as for clean looking writing. They are also used for fine-art drawing. Since they do not have to be sharpened, they are also popular with students. Mechanical pencils were first used in the 18th century, with many designs patented in the 19th and 20th centuries.