Throughout the past several decades, the world of rock music has grown. The time of The Beatles and Elvis' pop rock began to transform into a heavier form of rock music known as metal. In the dictionary, heavy metal is defined as "aggressive and heavily amplified rock music, commonly performed by groups that wear spectacular or bizarre costumes." Heavy metal music has pushed the envelope on how far music can be taken, and it is continuing to do so. While metal is not accepted by all people, those who follow it are able to find pure enjoyment and excitement from what it has to offer. Not all people will agree with what many metal music musicians have to say, but many can agree that on a basic level, metal music is all about the instruments, the loudness, and the presentation of the music. Before metal music even took form, the introduction of rock music was the first big step in metal's creation. As time passed, metal music did in fact begin as several metal bands began to rise. Over time, heavy metal music slowly began to change into the popular metal music of our modern day.

Before metal music even took off, the introduction of rock and roll music helped to bring about heavier rock. "In its purest form, Rock & Roll has three chords, a strong insistent back beat, and a catchy melody. Early rock and roll drew from a variety of sources, primarily blues, R&B, and country; but also gospel, traditional pop, jazz, and folk. All of these influences combined in a simple, blues-based song structure that was fast, danceable, and catchy." Some of the more notable rock and roll musicians include The Beatles, who came over to the United States during the British Invasion in the 1960s and began to heavily influence rock music; and Elvis PResley who is well known not only for his music, but for his live performances which include his infamous, and at the time, controversial "pelvis" shake. Other "British rockers such as The Who and The Kinks paved the way for heavy metal styles by introducing power chords and more aggressive percussion to the rock genre." While the original rock music of the 1950s and 1960s was certainly much lighter, in terms of how the instruments were played, artists stage presence, and the lyrics/themes of the songs, heavy metal music would not be where it is today without rock and roll.

Rock music is best viewed as if it were a family tree. While it is public knowledge that heavy metal came from traditional rock and roll music, it is also important to realize that rock and roll also helped to develop pop music. While heavy metal became a counter-culture form of music, popular music became widely accepted among parents and the younger generation of people because the pop artists were "carefully groomed and given inoffensive, catchy material to sing." The teen pop idols of the 1950s and 1960s mainly sang cover songs of other rock and roll/R&B artists of the time. In the same respect, heavy metal artists often wrote their own "in your face" lyrics; typically in a very political and angry fashion. Also, pop music was often more of a business than an artistic musical expression. It is rather sad to see business men get behind music with the only motivation being income. While not all of the pop artists were in the industry for the money, many of the business people behind them were. "Historically, the conflicting motives of business people and musicians have been a source of tension in the popular music industry." While one could admit that metal music (or all types of music for that matter) have artists who chose to solely play for profit, metal music often has more musicians who play for their love of music than their love of money. This is an easily noticed trait in heavy metal artists because they were often more underground, unpaid, and local artists in comparison to pop artists of the time. Even to this present day music generation, heavy metal and popular music tend to be complete polar opposites.

Throughout the year, metal music has taken on many different forms. The concept of sub-genres caused basic heavy metal to become more and more difficult to define. "Heavy metal branched out in so many different directions that new sub-classifications were created by fans, record companies, and fanzines, although sometimes the differences between the various sub-genres were unclear, even to the artist purportedly belonging to a given style." Heavy metal has become so eomplex to define that there are even sub-genres that separate one form of metal from another simply because of how fast or slow the music is played. Some different sub-genres of heavy metal includ, but are not limited to: thrash metal, hair metal, death metal, black metal, and gothic metal. Thrash metal is mostly a faster, punk rock influenced form of heavy metal introduced in the 1980s by the bands Metal Church and Venom. Slayer and Metallica are most likely the most popular bands coming out of the thrash metal era. Hair metal is one of the more interesting forms of heavy metal do to the fact that it was a "pop-based form of hard-rocking heavy metal." Hair metal got its name "due to the long, curled hair of band members."

As rock and roll music came along, music was able to continue progressing and artists began to form unknowingly the genre of heavy metal. "While the origin of the term 'heavy metal' is uncertain, an early usage of the term was by counter-culture writer William S. Burroughs." Heavy metal music truly became an art form more than just something to listen to. "Heavy metal, as an art form, is more than just music; it is as much visual as it is audible. While a painting is experienced visually, a symphony experienced audibly; a heavy metal band is experienced in both ways." This is made true simply by looking at a heavy metal bands live performances and album artwork. For example, KISS' live performance includes full costumes, stereophonics, and numerous other band and audience interactions. The fact of the matter is that when a heavy metal band gets up on stage, they are not just playing to the crowd; they also interact with them and make it an interactive show. As previously mentioned, other ways heavy metal is experienced visually is through artwork that many metal bands put out on their websites and in their CD covers.