Four main families(strings, woodwinds, brass and percussion)

Keyboard instruments

Piano, harpsichord, pipe organ and celesta

Pitched percussion instruments

Tympani(kettledrum), marimba, xylophone, vibraphone(vibes), glockenspiel(orchestra bells)

Unpitched percussion instruments

Snare drum, bass drum, cymbals, triangle, tambourine, gong, castanets and wood block

Brass instruments

Trumpet, French horn, trombone, euphonium and tuba

Plucked stringed instruments

Harp, classical guitar and cello

Bowed stringed instruments

Violin(highest pitched), viola, cello, double bass

Strings

Bowed stringed instruments and plucked stringed instruments

Single reed instruments

Clarinet and saxophone

Double reed instruments

Oboe, English horn, bassoon and contrabasson

Smallest

Flute and relative(smaller& higher pitch) piccolo