Rock music is one of the broadest descriptions of music around. Completely different bands, such as Greenday and Mayhem, both get put under the rock banner, but these to bands couldn't be more different. The Rock Banner is made up of many different types of music, and each one has its own different styles and techniques.
The first type of rock music is now known as classic rock. Classic rock is what most people think of rock 'n' roll. This genre is very blues based, and lots of songs feature the traditional 12 bar blues pattern, but unlike the blues, classic rock tends to be more focused around the key of G major, and the solos usually are more riff based, than the slow melodic blues style. Also vocals play a much bigger role in classic rock, than it did in the blues. Classic rock is very much an evolution of the blues. Some classic rock bands to try are; Led Zeppelin, ACDC, and Guns 'n' Roses.
Now days we have what is usually known as modern rock. Similar to classic rock in many ways, such as its blues origin, modern rock is an evolution of classic rock for the modern age. Unlike classic rock, it usually is more riff based, and sticks firmly in E minor pentatonic. Some modern rock bands to try are; Velvet Revolver, and the Darkness.
If rock music is the most generalised genre of music, metal music is the second. Metal music has evolved into many many different types of music over the years, more quickly than other genres. What originally started as metal is now known as classic metal. This was started by a band called Black Sabbath as music to scare people. Classic metal these days is pretty tame compared to what we have now, but then music like it was unheard off. Featuring heavy riffs, guitar solos, and unpleasant song lyrics, metal carved two groups for its self, those who love it, those who hate it. Some classic metal bands to try; Black Sabbath, Iron Maiden, and Judas Priest.
One of the most popular sub-genres of metal is trash metal. This took metals riffs and solos, and sped them up. The musicians were trashing their instruments, which is how it got its name. Thrash metal uses mainly 5 chords, aka power chords, and solos are usually in the pentatonic scale. The drums are usually very fast, and this was the first genre of music to use a double pedal, which allows a drummer to use his bass drum pedal at twice the speed. Some thrash metal bands to try; Megadeth, Metallica, Venom, and Motorhead (although some may argue these guys are classic metal, the ace of spades album is most defiantly thrash metal.)
Staying on the theme of speed, we can have a look at the punk revolution. By the 70s, music was getting very complex, with only the best musicians being able to make it (whether this is good or bad is up to you too decide), but punk changed all this. Punk featured very simple chords patterns, using power chords, simple but fast drumming, and a big stuff you to everyone. Most punk bands were rubbish, they knew it, and said so what? When punk hit its height it was a revolution, practically killing off the old prog rock bands. This punk is usually referred to as old skool punk. Some punk bands to try; The Sex Pistols, Bad Religion, and The Ramones.
During the 80s, punk has died down, and metal took over again, bringing the fast, complex thrash metal, and the classic rock inspired hair metal. This music is music for stadiums, big and bold. Featuring simple verses, usually with just a simple power chord progression, epic choruses, solos so long and epic that people could be brought to tears by them alone, and outfits and hair so mind bogglingly silly, hair metal fitted in with the new romantic style of the 80s. Unfortunately all the hair metal bands sunk into obscurity for reasons I shall explain next, so the only bands you'll be able to listen to are Bon Jovi, as the others are very hard to come across. Living on a Prayer is the perfect example of hair metal.
Music had very much got its talent back by the 80s, with punk dieing down and hair metal rising, a new revolution was due, and it came with a man named Kurt Cobain, a certain riff, and my favourite album of all time.
The 90s was the birth of grunge. Inspired by punk acts, like The Melvins, grunge came from Seattle in America and it became a world wide hit, led by the band Nirvana. Grunge is like punk, but it is usually a lot darker, features pop melodies, but blends them with cutting heavily distorted guitars, and very heavy drumming. The album Nevermind by Nirvana completely changed music at the time. So many bands formed simply because of this album, and grunge became the big thing, but the guitarist/singer/songwriter of Nirvana, Kurt Cobain, was what grunge was all about, and after his tragic suicide in 1994, grunge died with him. Some grunge bands to try; Nirvana, Soundgarden, and Bush.
The 90s was also the period where metal evolved the most though. While everyone else was moshing to the grunge sounds of nirvana, the few metal heads waited for their next big thing, and this came with Pantera. This band was very influential, and it inspired one of the most commercially successful genres of metal music, Nu-Metal.
Nu-Metal took metal, but ripped out the solos, and drop tuned their guitars. There are two different types of Nu-Metal, the KoRn camp and the Linkin Park camp. The KoRn camp drop tuned their guitars, which gives a deeper, heavier sound, and made the drums even louder and heavier than ever. Despite all this though, they added almost poppy melodies. Led by the band KoRn, this type of music has died out these days, with KoRn being the only band still going (but all their albums after 1997 have been below average). The other type of Nu-Metal takes a very pop approach to it. Its almost like pop-metal. Mixing metal riffs, epic choruses, pop melodies, and hip-hop influences, bands such as Linkin Park carved out a market for themselves with children under 13. Some Nu-Metal bands to try; KoRn, Linkin Park and Good Charlotte.
The 90s also gave birth to the most extreme type of music in my opinion, death and black metal. This genre originated from Norway, and takes influences from thrash metal bands, particularly Venom. The guitars and bass are usually drop tuned, to give a darker sound, and the drums almost always use a double pedal and a lot of snare. The vocals are usually screams all throughout, and the songs are about Satan worshipping, rape, murder, anti-Christian themes, and other nice topics like that! Although for some of these bands it is a joke, but for many it is not. Some black/death metal bands to try; Mayhem, Rotting Christ and Behemoth.
These days a new music genre has evolved, emotional music, or Emo for short. Heavily hated by most people who aren't Emo (unjustly) Emo is the fastest genre of music to get so hated. I happen to quite like Emo though. Emo is usually sad, and the lyrics are depressing. The music is in a minor key, and features broken chords quite heavily. The vocals are usually in a slight whiney voice, with lots of harmonising, and usually a very strong vocal hook in the chorus. Some Emo bands to try; Thrice, Scary Kids Scaring Kids, and Funeral For A Friend.
From Emo came metal/emocore. This takes elements of both Emo and thrash metal, and blends them together. The vocals are a mix of the death metal growl, and the Emo whiney style, and usually bands of this genre have two singers to compensate this. The music is very fast, usually relying on double pedal, and not stopping with it till the song ends. The riffs are usually a very fast, harmonising affair using two guitars. The guitar solos are very thrash metal, but with elements of hair metal in there, such as tapping, and epic feel. Some metal/emocore bands to try; Trivium, Killswitch Engage, and Mahcinehead.
Today a lot of the popular music scene is Indie rock. Indie rock is so called because the bands used to be very unpopular, and had to go on small independent labels, but these days the term means nothing, as most Indie bands are on major label deals. Indie rock usually features simple chord progressions, and clean guitar sounds. Some Indie bands focus on one melody, and work through that (Arcade Fire) but others use many different melodies at the same time, with a bass line to fit them together (Bloc Party). Like nearly all other types of music, power chords are used, and the lyrics are usually about real life. Some Indie bands to try; Bloc Party, The Subways, Arcade Fire, The Kooks, and Babyshambles.
Over time rock music has changed from just classic rock, to all the many genres we have now, and in this essay I have only covered the main ones, but my favourite thing about rock music is the diversity that it offers in styles and sounds of the music I choose, and although I enjoy other genres, like jazz, urban and classical, rock music remains my favourite.