What is percussive strumming?

I need to know real bad
What is percussive strumming?
Percussive strumming, often used on acoustics, is when you use the strings rhythmically instead of just harmonically. Often achieved by by muting the notes you%26#039;re holding with your left hand- you can mute by laying down the soft part of your right hand down against the strings and then strumming percussively. You can also mute strings with your left hand by not pressing the strings all the was down. Sometimes this is difficult to execute and if you%26#039;re near the 5th, 7th, or 12th frets you%26#039;ll likely hit harmonic tones instead of muting.