This article is about the rock band. ... 1988 is a leap year starting on a Friday of the Gregorian calendar. ... Rock and roll (also spelled Rock n Roll, especially in its first decade), also called rock, is a form of popular music, usually featuring vocals (often with vocal harmony), electric guitars and a strong back beat; other instruments, such as the saxophone, are common in some styles. ... Heavy metal is a form of music characterised by aggressive, driving rhythms and highly amplified distorted guitars, generally with grandiose lyrics and virtuosic instrumentation. ...