ROCK MUSIC

The origins of rock 'n' roll are as foggy as the genre is popular; the term was coined in 1955 by Alan Freed, a disc jockey from Ohio. The oldest form of rock 'n' roll (1950s) was a mixture of R&B, country and rockabilly (it was just called hillbilly music back then), only it was faster, louder and 'dangerous'. The man at the forefront of this genre was (and still is) Elvis Presley, followed by personalities like Chuck Berry and Little Richard.
The rock scene in the 50s was more about shock value, which included fashion statements, sexually-oriented lyrics and dance moves catering to a young audience in particular. There were generations of largely American and European artists, each influenced by their predecessors, trying to make something better, in rock music. Whether that was through clothes, the rhythm or harnessing and even catalyzing political agenda, rock music was, is and will be, all about shocking the current generation.

The one great push for music into the whole rock band scene was arguably done by The Yard birds. The band includes the three guitarists that helped shape rock music - Jimmy Page, Jeff Beck and Eric Clapton. Each member contributed heavily to the band as well as creating entire separate realms of rock, namely the band Led Zeppelin (founded by Jimmy Page).

All in all, rock can be largely sub-categorized into the following types or styles. Bear in mind that they are more of less styles of rock rather than completely different genres, and that an artist or a band can be found in more than one style (like Led Zeppelin can be found under hard rock, psychedelic rock and folk rock. Queen falls under progressive rock and glam rock).

Alternative rock is anything that peaked for brief periods of time and was out of the ordinary, even by rock standards. This includes grunge, indie, new wave, punk and goth to name a few. Alternative rock can be defined more through movements rather than individual bands.

Art rock, which is the early form of psychedelic rock and progressive rock. It is led by the bands Exploding Plastic Inevitable, Pink Floyd and The Jimi Hendrix Experience (Jimi was also known as the pioneer of acid rock).

Arena rock, which is just a different way to see the greater rock bands of old: under heavy lighting, dynamic stage acts and crowd inclusion. The style focuses more on the stage (like Woodstock) than any band in particular.

Metal is perhaps the branch of rock with the most number of offshoots. It is believed to be initiated by Black Sabbath. It also includes Iron Maiden, who are a part of the heavy metal movement called New Wave of British Heavy Metal.

Glam rock can encompass a wider range of other styles of rock, and add feminine detailing and promiscuity. This includes David Bowie, Queen, Elton John and T. Rex. There's also glam metal with Alice Cooper and Aerosmith.

These main styles have a wide array of sub-categories, giving you hundreds of styles in rock music, like death metal, British invasion, southern rock, roots rock, college rock, Christian rock, etc.