Pop music (a term that originally derives from an abbreviation of popular) is usually understood to be commercially recorded music, often oriented towards a youth market, usually consisting of relatively short and simple love songs and utilizing technological innovations to produce new variations on existing themes. Pop music has absorbed influences from most other forms of popular music, but as a genre is particularly associated with the rock and roll and later rock style.
Hip hop is a cultural movement that originated in the working class communities of New York City, United States, in the late 1970s.[1][2][2] DJ Afrika Bambaataa first outlined the five pillars of hip-hop culture: MCing, DJing, breaking, graffiti writing, and knowledge.[3][4][5][6] Other elements include beatboxing, hip hop fashion, and slang. Since first emerging in the South Bronx, hip hop culture has spread around the world.[7] When hip hop music began to emerge, it was based around disc jockeys who created rhythmic beats by looping breaks (small portions of songs emphasizing a percussive pattern) on two turntables, which is now more commonly referred to as sampling. This was later accompanied by rap (a rhythmic style of chanting or poetry more formally in 16 bar measures or time frames) and beatboxing, a vocal technique mainly used to imitate percussive elements of the music and various technical effects of hip hop DJs. An original form of dancing and particular styles of dress arose among lovers of this new music. These elements experienced considerable refinement and development over the course of the history of the culture.

The relationship between graffiti and hip hop culture arises from the appearance of new and increasingly elaborate and pervasive forms of the practice in areas where other elements of hip hop were evolving as art forms, with a heavy overlap between those who wrote graffiti and those who practiced other elements of the culture.

Heavy metal (often referred to simply as metal) is a genre of rock music[1] that developed in the late 1960s and early 1970s, largely in the United Kingdom and the United States.[2] With roots in blues-rock and psychedelic rock, the bands that created heavy metal developed a thick, massive sound, characterized by highly amplified distortion, extended guitar solos, emphatic beats, and overall loudness. Heavy metal lyrics and performance styles are generally associated with masculinity and machismo.[3]

The first heavy metal bands such as Led Zeppelin, Black Sabbath and Deep Purple attracted large audiences, though they were often critically reviled, a status common throughout the history of the genre. In the mid-1970s Judas Priest helped spur the genre's evolution by discarding much of its blues influence; Motörhead introduced a punk rock sensibility and an increasing emphasis on speed. Bands in the New Wave of British Heavy Metal such as Iron Maiden followed in a similar vein. Before the end of the decade, heavy metal had attracted a worldwide following of fans known as metalheads or headbangers.

In the 1980s, glam metal became a major commercial force with groups like Mötley Crüe. Underground scenes produced an array of more extreme, aggressive styles: thrash metal broke into the mainstream with bands such as Metallica and Megadeth, while other styles like death metal and black metal remain subcultural phenomena. Since the mid-1990s, popular styles such as nu metal, which often incorporates elements of grunge and hip hop; and metalcore, which blends extreme metal with hardcore punk, have further expanded the definition of the genre.