Noise Pop is a spin-off form of the musical genre known as Noise.
Noise Pop is characterized by:
Tape loops
Heavy use of distortion
Odd (possibly broken) meter
Greater use of guitars, rather than keyboards
Loud, distorted drums, emphasizing the snare
Experimentation (especially in how the guitar is played)
Droning, detuned guitars
Bizarre ambient noises (and not necessarily quiet ones)
Loud instrumentation (a My Bloody Valentine concert occasionally reached 100 dB)
Catchy melodies
Indie-pop style melodies and song structure
Typically soft vocals, mostly female
Noise Pop came into vogue in the mid-nineties after Noise recieved underground popularity, predominantly in Japan (thanks to acts like Merzbow and Melt Banana) and the U.K. Although it never reached mainstream popularity, Noise Pop is still popular on the Indie circuit.
Noise Pop has similarities to other forms of Indie Rock, such as Lo-Fi, Shoegazing, and Dream Pop. On occasion, even the Cocteau Twins have been called Noise Pop (?). Even more interesting is Noise Pop is sometimes confused with Digital Hardcore (fewer guitars and more Punk rock influence) and Industrial (more depressing and seething)
Some of the popular Noise Pop acts:
My Bloody Valentine
Garbage (not typically classified thus but has enough similarities to warrant here)
Early Badly Drawn Boy