MUSICAL INSTRUMENTS
A musical instrument is a device that has been constructed or modified with the purpose
of making music. In principle, anything that produces sound, and can somehow be
controlled by a musician, can serve as a musical instrument; but the expression is
reserved generally to items that have that specific purpose.
The academic study of musical instruments is called organology.
Instruments are often divided by the way in which they generate sound:

Wind instruments generate a sound when a column of air is made to vibrate
inside them. The frequency of the wave generated is related to the length of the
column of air and the shape of the instrument, while the tone quality of the sound
generated is affected by the construction of the instrument and method of tone
production. The group is typically subdivided into Brass and Woodwind
instruments.
A Brass instrument is a musical instrument whose tone is produced by vibration
of the lips as a player blows into a tubular resonator. Nowadays they generally
come in one of three families:
I.
Natural brass instruments, where the player can only play notes in the
instrument's harmonic series, for example the bugle.
The trumpet was a natural brass instrument prior to about 1795,
and the French horn before about 1820.
II
Valved brass instruments use a set of valves (typically 3 or 4 but as many as 7 or
more in some cases) operated by the player's fingers that introduce additional
tubing into the instrument, changing its overall length. This family includes the
modern trumpet
cornet [closely resembles the trumpet]
flugelhorn [brass instrument resembling a cornet but with a wider, conical bore].
euphonium [its appearance is very similar to that of a tuba]
tuba [the largest of the low-brass instruments]
sousaphone [valved brass instrument with the same tube length as a tuba, but
shaped differently so that the bell is above the head]
mellophone [The instrument has three valves. However, the valves are pressed
with the right hand for mellophone, instead of the left for a concert horn. Also,
although some of the mellophone fingerings are the same as those of the concert
horn, they generally resemble trumpet fingerings more than horn fingerings]
III.
Slide brass instruments use a slide to change the length of tubing. The main
instrument in this famility is the trombone
and the slide trombone's ancestor the sackbut. Some modern trombones also have
rotary valves in addition to the slide. The folk instrument the bazooka is also in
the slide family.
In the past, a fourth type was common:
IV. Keyed or Fingered brass instruments used holes along the body of the
instrument, which were covered by fingers or by finger-operated pads (keys) in a
similar way to a woodwind instrument. These included:
Cornett
serpent [wind instrument with a mouthpiece like a brass instrument but side holes
like a woodwind instrument] and keyed trumpet [brass instrument that,
contrary to the traditional valved trumpet, uses keys ].
Some other brass instruments
alphorn (wood)
conch (shell)
shofar (horn) [ram's horn that is used for religious purposes]
Didgeridoo (wood, Australia) [It is sometimes described as a natural wooden
trumpet or "drone pipe". Musicologists classify it as an aerophone ]
Wagner tuba
A woodwind instrument is a musical instrument in which sound is produced by
blowing through a mouthpiece against an edge or by a vibrating reed, and in
which the pitch is varied by opening or closing holes in the body of the instrument.
Woodwind instruments were originally made of wood, as the word woodwind
implies.
There are three main sorts of woodwind instrument:
1.
Single Reed instruments [when air is forced between the reed and the
mouthpiece, the vibrations create the sound].
Single reed instruments include
the clarinet
and saxophone
2.
Double Reed instruments use two precisely cut, small pieces of cane
joined together at the base. The finished, bound reed is inserted into the
top of the instrument and vibrates as air is forced between the two pieces
of bound cane. There are two sub-families:
Exposed double reed instruments, where the reed goes between the player's lips.
The oboe
cor anglais (also called english horn)
and bassoon
make up the more popular instruments within this family
3.
Flute woodwind instruments where the sound is produced by blowing
against an edge. There are two subfamilies:
Open flute family, where the player uses their lips to form the stream of air which
goes directly from the players lips to the edge, e.g. the transverse flute
Modern flutes are made of either silver or gold.
Closed flute family, where the instrument forms and directs the stream over the
edge. This family includes whistle
and the recorder family [flute-like woodwind musical instrument. Contrariwise,
the flute is a recorder-like woodwind musical instrument]

Percussion instruments create sound, with or without pitch, when struck. The shape
and material of the part of the instrument to be struck and the shape of the resonating
cavity, if any, determine the sound of the instrument. Most percussion instruments
have a distinct tone; even drums are tuned. However, a distinction is usually made
based on whether the instrument can play a definite pitch or not.
1]
Instruments which play a definite pitch:
timpani
xylophone
marimba
vibraphone
bell
crotales (or antique cymbals) and glockenspiel
2]
Instruments which in general do not play a definite pitch:
snare drum
bass drum
afuche
castanets
claves [consisting of a pair of short, thick wooden dowels], cymbal
güiro
maracas
mendoza [constructed from a stout pole affixed to a heavy boot at the base], ratchet
[Operating on the principle of the ratchet device, a gearwheel and a stiff board is mounted
on a handle, which can be freely rotated], temple blocks [its sound is similar to that of
the wood block, although temple blocks have a darker, more "hollow" timbre], tom-tom
triangle
vibraslap
washboard
whip [consisting of two wooden boards joined by a hinge at one endand], wood block

String instruments generate a sound when the string is plucked, strummed,
slapped, etc. The frequency of the wave generated (and therefore the note
produced) usually depends on the length of the vibrating portion of the string, the
tension of each string and the point at which the string is excited; the tone quality
varies with the construction of the resonating cavity.
Instruments where the strings are usually bowed
Cello
Electric cello
Crwth
Double Bass
Fiddle
Gadulka (Bulgaria)
Gudok (Russia)
Nyckelharpa
Viol
Viola
Viola d'amore
Violin, Violotta [tenor viola].
Guitar and lute posed side-by-side
Instruments where the strings are usually plucked
Balalayka (Russia)
Banjo (American)
Bouzouki (Greece)
Chitarrone (Mexico)
Electric bass
Guitar
Gusli (Russia)
Harp
Harpsichord (Europe, keyboard instrument)
Kora [21 string harp-lute used extensively by Mandingo peoples in West Africa]
Koto (Japan)
Lute (Europe)
Mandolin
Musical bow
Oud (Middle East, Greece)
Pipa (China)
Sarod
Shamisen (Japan)
Sitar (India)
Ukulele (Hawaii)
Veena (India)
Zither (China)
Instruments where the strings are usually struck
Clavichord (keyboard instrument)
Hammered dulcimer
Piano (keyboard instrument)
Santur (Persia), Warr guitar.

Voice, that is, the human voice, is an instrument in its own right. A singer
generates sounds when airflow from the lungs sets the vocal cords into oscillation.
The fundamental frequency is controlled by the tension of the vocal cords and the
tone quality by the formation of the vocal tract; a wide range of sounds can be
created.

Electronic instruments generate sound through electronic means. They often
mimic other instruments in their design, particularly keyboards.