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In graphic art, drawings are often constructed from a perspective, and there are one-point, two-point and three-point perspectives. Perspectives allow the "artist" to draw in three dimensions. The stationary point is where the "observer" stands to view the picture. The horizon line is the line that creates the sense of a horizon on the page, moving horizontally or side-to-side, and the vanishing point is the place where the lines that do converge seem to "disappear" into the horizon.
A one-point perspective in a drawing has a single vanishing point. A vanishing point is when two lines that are not parallel to the subject of the drawing (or "image"), run together or "converge," no longer separate lines—often moving in a direction opposite from the viewer's perspective.
All lines parallel with the viewer's line of sight recede to the horizon towards this vanishing point.
To be better able to visualize it, the lines look like railroad tracks running away from you that seem to meet—like lines at the bottom of a "V," and disappear, usually at the horizon line.
The drawing with a two-point perspective is slightly more complicated. Here there are lines placed parallel to "two different angles." The image's lines come from two different points, and this type of drawing has two vanishing points.
...as a result the sides look as if they are slowly fading away into the distance.
If you change the location of the vanishing points, you can make the image or object larger or smaller.
The three-point perspective is similar in several ways to the two-point perspective. It, too, has a horizon line and a stationary point. Looking at a building that is drawn with three-point perspective, it may seem that as you are looking, the lines that define the sides of the building draw your gaze upward, moving ever closer to each other, as if they would eventually meet, once again like lines at the bottom of a "V." Sometimes this kind of drawing is presents a 3/4 view. This perspective does not necessarily give the viewer the sense of looking at the image straight on, but the observer may feel as if he/she is looking from an angel. This drawing has three vanishing points. Two fall on either side of the object, but the third rises above the object and may or may not be seen to converge depending on how tall the picture is.