The majority of musical instruments found in a music instrument store fall into one of six major categories. These are bowed strings, woodwind, brass, percussion, keyboard and the guitar family.
Bowed Strings: the violins, the violas, the cellos and the double basses
Woodwind: flute, oboe, clarinet, bassoon
Brass Instruments: trumpet, fresh horn, trombone, tuba
Percussion Instruments: tuned, indefinite pitch
Keyboard Instruments: plucked, struck, aerated, electronic
Guitar Family: six-stringed and the four-string bass guitar.
clipped from: themusicinstrumentstore.com