Three-dimensional means that two dimensions plus height form a volume. Dimension, also called dimension, is the number of independent parameters in mathematics. In physics and philosophy, the number of independent space-time coordinates. Dimension 0 is an infinitesimal point with no length. 1 dimension is an infinite straight line with only length. 2-D is a plane, which is an area composed of length and width (or partial curves).

Broadly speaking, a dimension is the number of related abstract concepts of things. Related abstract concept refers to an abstract concept connected by multiple abstract concepts, which is related to any abstract concept that constitutes it. The number of abstract concepts that make up it is its change dimension, such as area. The basis of this concept is that everything is related.

/kloc-in the 9th century, mathematicians discovered fractal, thus creating a new dimension, namely fractal dimension. People realize that dimensions are not only integers, but also fractions and even irrational numbers. Professor Stephen Hawking, a famous British physicist, has this explanation: it is like a hair, which is a one-dimensional line from a distance. Under the magnifying glass, it is really three-dimensional; If we face time and space, if we have a magnifying glass with high magnification, we should also be able to reveal other possible 4-and 5-dimensional spaces, up to 1 1 dimensional space.