Van Hagar is an alternative name, typically used disparagingly, given to the band Van Halen after its original lead singer, David Lee Roth was fired and the band brought in veteran rock guitarist and singer Sammy Hagar.
The style of Hagar was quite different than the wildly flamboyant Roth, who used his impressive flexibility to do high jump kicks and other martial arts-style moves while singing on stage. Hagar was more of an old-school personality, with plenty of enthusiasm and years of chops playing for the hard rock group Montrose, the supergroup HSAS, and a solo career that included the top iconic hit "I Can't Drive 55".
The differences in vocal styles was a bit of a shock when the band changed out the lead singer, although the addition of another accomplished guitarist did broaden the band's sound.
As for me, while I do prefer the original lineup, I can appreciate several of the hits that Hagar brought to the table for Van Halen.
Iron Noder 2017