The bass guitar is a transposing instrument that is larger than a guitar and sounds an octave lower than written. It commonly has 4 strings and is played using a bass clef. There are different varieties of basses including those created by Fender and Gibson. The bass guitar was invented in the 1930s and uses an amplifier to be heard at louder volumes. It can be played by plucking or using a thumb and fingers, with various techniques used including slapping and tapping. Popular bassists and songs are mentioned.