The Force

The Force is a metaphysical energy field that envelops (and therefore originates in) the Star Wars continumn. It is the source of all power for the Jedi and the Sith, and is intimately connected to all life in that universe. Anakin Skywalker was said to have been concieved by midi-chlorians, the biological manifestation of the Force.

More about the Force at Wookieepedia.