R & B
Throughout the 20th century, R & B has been the largest influence on popular music all over the world. The influence can even be seen in forms of rock, country and western, gospel, and jazz. Despite the fact that there are many styles, there are common musical and social elements that link them.
The musical rhythm is clearly the most important and distinguishing element. All the genres of R & B typically depend upon a four-beat measure and a backbeat (the accentuation of beats two and four).
During the 1980s and 1990s, superstars like Prince, Michael Jackson, and Janet Jackson created a new style by borrowing from funk and other dance styles. Rap was the most significant development in popular music during this time period. The roots of rap lie in African and African American verbal games.
Rock n Roll
The category of Rock music describes a group of related music styles that have dominated popular music in the Western Hemisphere since the 1950s. Rock music began in the United States but has been distinctly shaped by many other styles ranging anywhere from gospel to classical music. Rock 'n' roll became the first style of music to attempt to appeal directly to young people. It developed through mixing African American rhythm and blues with American country music.
Rock 'n' roll was truly made a world-wide obsession by Elvis Presley. Later, groups like the Beatles and the Rolling Stones added their own distinctive touches to rock 'n' roll. "Soul" also developed during this period through artists such as Aretha Franklin. She created a blend of R & B and gospel music to create the new style. In the late 1970s, a new version of rock 'n' roll, labeled "punk rock," developed. During the next two decades, superstars emerged, like Michael Jackson and Madonna, who began filling huge stadiums for concerts.
The central and linking instrument of most kinds of rock music is the electric guitar.. Other instruments that are common in rock music are the electric bass guitar, various keyboard instruments (including the electric piano, organ, and synthesizer), and the drum set.