ISO 128 is an international standard (ISO), about the general principles of presentation in technical drawings, more specific the graphical representation of objects on technical drawings.

Since 2003 the ISO 128 standard contains twelve parts, which had been initiated between 1996 and 2003. It starts with a summary of the general rules for the execution of technical drawings, as well as presenting the structure. Further it describes basic conventions for lines, views, cuts and Sections, and different types of engineering drawings, such for mechanical engineering and construction in architectural, civil engineering, shipbuilding etc. It is applicable to both manual and computer-based drawings, but it is not applicable to three-dimensional CAD models.

The ISO 128 replaced the previous DIN 6 standard about drawings, projections and views, which was first published in 1922, and later updated in 1950 and 1968. The ISO 128 itself was first published in 1982, contained 15 pages and "specified the general principles of presentation to be applied to technical drawings following the orthographic projection methods". Several parts of this standard have been updated by individual parts and eventually the last parts and the whole standard as a whole has been withdrawn by the ISO in 2001.

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