Alternative metal (or alt metal) is a style of music of usually metal music. It is unconventional to other metal genres. However, some bands may instead be alternative rock with metal influences and loud guitar riffs. Those bands are like Chevelle, Breaking Benjamin and stuff. Typical bands like Mudvayne, System of a Down, Nothingface, etc are more unconventional metal. These bands might do singing, growls, yells, or screaming (not shrieking ones), heavy riffs, and angry drumming and sound. But bands like Chevelle, Three Days Grace, Breaking Benjamin, Jane's Addiction and stuff are more alternative rock sounding.