The term compression refers to the reduction in the length or thickness of a body. External influences are responsible for this deformation. The compression is the result of a compressive force.
The opposite of compression is elongation, in which the dimensions of a body increase. Both processes are directly related. If a body is compressed in the longitudinal direction, its cross-section increases (elongation) so that the volume is approximately maintained. This principle is called transverse contraction.
The deformation resistance of the body counteracts the compressive force. If the compressive force on a body is too great, it can buckle.