in short, you can turn any number of channels of power into a smaller number of channels with more power per channel
without damaging the amp. the relationship doesn't always have to be 4-to-2. it could also be 2-to-1 or 4-to-1 depending on the features of the amp. and like jerseycat said, in this case if you have an amp rated at 100 watts per channel, and you bridge all four channels into 1, you'll have 400 watts total to feed 1 speaker.
http://www.crutchfield.com has more info and FAQ's on common audio terminology.
hope this helps!
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1995 GL Zetec MTX
KKM Intake
Superchip (yay!)
ASP Underdrive Pulley (to be installed soon)
AR 16x7 w/ Dunlop W-10 (205.50.16)
Viper 500+ Alarm
Sounds by: Pioneer CD/Polk dB/MTX Subs/Alpine Amp
Richbrook Shift Knob
"Recontented" Factory Instrument Cluster w/Tachometer (need to adjust mileage)
"Cheapo" Foggies
98+ Sail Panels (to be installed...maybe)
