The humble distortion pedal is the essence of rock guitar playing.  But many people wonder what is the difference between distortion and overdrive? The most common explanation is that distortion is more overdriven and "hot" sounding, while an overdrive pedal is usually more warm and bluesy.

 

Overdrive pedals generally offer more sustain than actual distortion. But this is of course a generalization. Depending on the make and model, some distortion pedals off more of a sustained overdrive sound than others.