What is Peak Oil?

Global oil discoveries peaked in the 1960s and are rapidly declining as oil becomes harder to find.
Today there is a growing gap between new oil discoveries and production.
US oil production peaked around 1970. A global peak in oil production is imminent.

Colin Campbell: "The term Peak Oil refers the maximum rate of the production of oil in any area under consideration, recognising that it is a finite natural resource, subject to depletion."