The guitar is one of the most popular instruments in the world and has had a major influence on modern music.  The average price for a quality entry-level guitar is $200-$400.  The guitar can often be found in the popular and folk music in many countries and it may be part of the rhythm section in jazz ensembles.  The three types of the modern acoustic guitar are the classical (with nylon strings) guitar, the steel string guitar, and the archtop guitar.  The most famous guitar brands are Martin, Gibson, B.C. Rich, and Fender.