Last modified on 28 March 2009, at 11:20


A front is a boundary or transition zone between two air masses of different density, and thus (usually) of different temperature. A moving front is named according to the advancing air mass, e.g., cold front if colder air is advancing.[1]

In military usage, the term is also used in wartime refer to the geographic area where the bulk of fighting takes place (as opposed to a rear area).