Hard rock is a blues based subgenre of Rock n Roll. Often hard rock is influenced by British Blues, which is a style of blues played with more modern instrumentation. Although technically a sub-genre itself, hard rock contains many of its own sub genres such as grunge and heavy metal. The main characteristic shared by many of these sub-genres and music acts is the loudness of the music. Louder more powerful drumming, loud vocals, and heavier guitar riffs are generally used in hard rock.

Many British rock bands of the 60's such as the Beatles, The Who, the Rolling Stones, and Cream laid the groundwork for what would eventually become hard rock in the 1970's. In the 60's and early 70's British bands like Black Sabbath took British rock and mixed it with a louder form of blues rock to eventually come up with the Hard Rock genre. Some early standout hard rock albums are The Who's Live at Leeds, Led Zeppelin I, and Deep Purple's first album Shades of Deep Purple.

In the early 1980s hard rock and one of its sub genres, metal and glam rock, became very popular. With bands like Motley Crue, Def Leppard, and Van Halen all becoming household names hard rock became very successful commercially. Towards the end of the 80's hard rock band Guns N Roses became very popular and reached the top of the charts with their album Appetite for Destruction.

Guns N Roses and fellow hard rock band Metallica continued to appeal to a large audience throughout the early 90s and became an influence for many hard rock bands to come. As time went on bands took their early hard rock influences and mixed them with other genres of music to create various subgenres of hard rock. Bands like Rage Against the Machine, The Red Hot Chili Peppers, and White Zombie all are great examples of popular music from the 90s with hard rock roots.

Currently there are a number of bands that remain faithful to their love of hard rock music and this shows. Hard rock doesn't appear to be slowing down anytime soon with successful bands like Wolfmother and Jet channeling their appreciation for early hard rock acts in their albums.

Hard Rock has maintained its popularity over the years mainly because of the large variety of sounds and types of music. Hard rock will continue for many years to come because of its large appeal to so many people and because so many bands have been positively influenced by it.