Editing P wave (section)

{{Short description|Type of seismic wave}}
{{hatnote|This article is on the type of seismic wave. For the term used in electrocardiography, see [[P wave (electrocardiography)]]. P wave can also refer to a type 
of electronic wave function in atomic physics; see [[atomic orbital]].}}
{{Earthquakes}}
[[Image:Onde compression impulsion 1d 30 petit.gif|thumb|upright=1.4|Plane P wave]]
[[Image:Ondes compression 2d 20 petit.gif|thumb|upright=1.4|Representation of the propagation of a P wave on a 2D grid (empirical shape){{clarify|date=November 2017}}]]

A '''P wave''' ('''primary wave''' or '''pressure wave''') is one of the two main types of elastic [[Body wave (seismology)|body waves]], called [[seismic waves]] in seismology. P waves travel faster than other seismic waves and hence are the first signal from an earthquake to arrive at any affected location or at a [[seismograph]]. P waves [[Continuum mechanics|may be transmitted through]] gases, liquids, or solids.