modern pop music grew out of 1950's rock and roll, (for example chuck berry, bo diddley and little richard) and rockabilly (for example elvis presley and buddy holly). in the 1960s, the beatles became a famous pop music group. in the 1970s, other styles of music were mixed with pop music, such as funk and soul music. pop music generally has a heavy (strong) beat, so that it is good for dancing. pop singers normally sing with microphones that are plugged into an amplifier and a loudspeaker.