N312RC has it. For transport certified aircraft V1 is the speed on the runway that allows for the pilots to react to a situation and bring the aircraft to a halt on the remaining runway. The speed is greater than the minimum control speed on the ground to allow for critical engine failure etc.
Two accidents regarding V1 are worth a mention. A good example of why not to abort a takeoff beyond V1 was demonstrated by a DC-10-30 at Nagoya a few years back. The other is the Concorde at CDG earlier this year, by sticking to the 'continue' restriction of an airspeed above V1 the aircraft became airborne with a burning wing.
The DC-10 would have completed a circuit and landed, the Concorde would not have stopped on the runway, but MAY have been survivable. The Concorde Captain did EXACTLY as he was trained, however.
Hope this helps.