Jrock is the short version for "Japanese
rock", which includes Visual Kei, normal and alternative
rock, but from Japanese bands. The term sometimes includes Japanese
metal bands (such as Maximum the Hormone), but it's more rarely seen.
The most
popular Jrock band in
Japan is SID, but the GazettE has a lot of fans outside the country. They
play Visual Kei and DOES plays normal rock in Japanese.