It really started in the late nineties with bands like Korn, Limp Bizkit, Linkin Park fusing metal music with rap and rock.
But early 1990s bands like Faith No More kicked it off.
Nu-metal is a little slower than traditional heavy metal and thrash. It's hip-hop influenced and basically anything goes.
Nu-metal bands use loads of vocalists and sample other artists. But the guitar still rules.
Fans often dress like skateboarders - they're particularly big on chains and baggy trousers.
Words to use include minging and stonking (both mean smelly)!