Symmetry is the harmony of shape and size between parts of an object or image. It can be defined as everything that which can be divided into parts, the parts being exactly the same. If we draw a straight line dividing a figure in half and the two parts, when placed one on top of the other, are equal, we can say that the figure is symmetric.
Symmetry is present everywhere, whether in nature, the arts, architecture or mathematics.
Mathematical symmetry, for example, consists of the rule of disposing two identical figures that correspond point to point. In this context, the object moves, but distances, angles, sizes and shapes are preserved for symmetries.
In geometry, it is called symmetry axis to the line, imaginary or real, that divides the figure or object into identical (symmetric) parts.
In the aesthetic field, symmetry is responsible for providing harmony to an image, and consequently, its beauty. The more symmetrical an object or figure is, the more beautiful it tends to be considered.
There are four types of symmetries: reflexive, rotational, radial and bilateral.
see the Definition of Axis.
Symmetry Types
reflective symmetry
As the name implies, it has to do with the reflection. It is also called axial symmetry or mirroring. In this kind of symmetry, the axis functions as a divider of the image of its reflection.
rotational symmetry
Also called central, rotational symmetry is characterized by the presence of a fixed point (centre of symmetry) around which the figure can rotate while maintaining the same aspect.
radial symmetry
Radial symmetry is used in the field of biology to classify living things. In radial-type symmetry, any trace, as long as it passes over the central point, will divide the body of the living being into equal parts.
bilateral symmetry
Bilateral symmetry is commonly used in biology to classify and describe living things. This type of symmetry classifies figures, beings or objects when they have only a single axis of symmetry.
symmetry and asymmetry
Symmetry and asymmetry are antonyms, that is, they have opposite meanings.
Symmetry is the conformity and correspondence between position, shape and measure in relation to an axis. It is the existence of harmony between two or more parts.
Asymmetry, in turn, would be the absence of symmetry, that is, when there is no correspondence between the parts, being disproportionate or not harmonious.
See also:
Definition of Geometry
Definition of Anthropometry