In Ancient Times (meaning in the WWII era) engineers were taught about two types
of waves. Longitudinal waves seemed to be applicable to sound in gasses, and
Transverse waves seem to be applicable to electromagnetic propagation. Both
waves were utilized in elastic media, and still form the basis of a huge
petrochemical exploration industry. The 1 "point or dimensional" (longitudinal)
and the 2 "point or dimensional" transverse waves do pretty well in explaining
a lot of phenomena.
A convoluted argument can be developed (based on associative division algebras -
of which there are only three) that there ought to exist a third kind of wave -
a 4 "point" wave, herein described as a "Torsion' wave. Indeed, such 4 point
waves have been extracted from solutions to Maxwell's equations, and have been
measured in dual polarized Ring Lasers. They also should appear in elastic
media, but so far only limited utilization has been made of Torsion waves have
been made in any practical application.