Geometric Dimensioning and Tolerancing is a set of rules and GD&T symbols used on a drawing to communicate the intent of a design, focusing on the function of the part. Using GD&T results in a more accurate design, larger tolerances for less important design features, and cost savings for manufacturing. The user can go through the materials which is theoretical and comprising of symbols. The user, while detailing should use this GD & T.
ISO defines GD&T as “geometrical product specifications (GPS)—Geometrical tolerancing—Tolerancing of form, orientation, location and run-out.” In short, “geometrical product specifications” refer to the shape, size, and positional relationship of a product, while “tolerance” means the allowable error. “Geometric tolerance” is characterized by a definition that includes the allowable errors for the form and position in addition to size.
