Technical drawing, also known as drafting or draughting, is the act and discipline of composing plans that visually communicate how something functions or is to be constructed.
Technical drawing is essential for communicating ideas in industry and engineering. To make the drawings easier to understand, people use familiar symbols, perspectives, units of measurement, notation systems, visual styles, and page layout. Together, such conventions constitute a visual language, and help to ensure that the drawing is unambiguous and relatively easy to understand.
This need for precise communication in the preparation of a functional document distinguishes technical drawing from the expressive drawing of the visual arts. Artistic drawings are subjectively interpreted; their meanings are multiply determined. Technical drawings are understood to have one intended meaning.
A drafter, draftsperson, or draughtsman is a person who makes a drawing (technical or expressive)
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Engineering Drawing Basics
Chapter 1 Orthographic Projection