Root mean square (rms) is, literally, the square root of the mean of the square of a value. It is a process for calculating an average value for a fluctuating value (such as ac voltage or current.) The term rms power is referred to as the average power. A power amplifier rated as having "200 watts rms power" really puts out 200 watts of continuous sine wave power.
In other words, when you buying a speaker always look for a high RMS, WATTS doesn't mean everything..The higher the RMS the better and stronger the speaker..I hope that helped ya a lil
. I got the definition from the net 8) ...