Perspective
Representation of depth on a flat surface, typically through lines that converge toward one or more vanishing points.
In practice
Perspective creates the illusion of depth on a flat surface. In linear perspective, parallel lines receding from the viewer appear to meet at vanishing points on the horizon, and objects shrink with distance. Designers use it in product sketches, architectural drawings and interface illustrations: a chair drawn in two-point perspective shows two sides receding toward points on either side, so it reads as a solid object.
Often confused with isometric
Perspective makes distant things smaller and parallel lines converge; isometric drawing keeps parallel lines parallel and sizes constant, so nothing recedes.
Try this
Draw a box in one-point perspective with a single vanishing point, then add a second box farther away.