Orthographic projection

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Orthographic projection illustrates three-dimensional objects on flat surfaces to showcase their attributes and size accurately. In technical drawing, two primary perpendicular planes depict projections of models: a vertical and a horizontal one. These planes divide space into four dihedral or quadrants. Each dihedral consists of two perpendicular half-planes numbered counterclockwise, opposite to the clock's hand movement. Gaspar Monge developed the method of portraying objects in two perpendicular half-planes, called the Mongean method. Most countries using this approach adopt orthographic projection in the first dihedral. In Brazil, ABNT advises representation in the 1st dihedral, while some nations, such as the United States and Canada, depict their technical drawings in the 3rd dihedral.