Theory:

Musical instruments:
 
What is music?
Some sounds are pleasing to the ear and make us happy. The sound that provides a pleasant sensation to the ear is called music.
The regular patterns of vibrations produce music. Musical instruments are categorized into four types, as given below.
  • Wind instruments
  • Reed instruments
  • Stringed instruments
  • Percussion instruments
Wind instruments:
 
In a wind instrument, the sound is produced by the vibration of air in a hollow tube. The frequency of the sound is varied by changing the length of the vibrating air column. Trumpet, Flute, Shehnai and Saxophone are some well-known wind instruments.
 
Bansuri_bamboo_flute_23inch.jpg
Flute made of wood
  
trumpet-brass-instrument-music-instrument.jpg
Trumpet
  
Reed instrument:
 
A reed instrument contains a reed(a thin piece of wood or metal at the end of some musical instruments which produces a sound). Air, which is blown through the instrument, causes the reed to vibrate, which produces the specific sound. Examples of reed instruments include Harmonium and Mouth Organ.
 
music-technology-shine-instrument-metal-close-857213-pxhere.com.jpg
Mouth organ
 
Pakistani_Qawwali_Harmonium.jpg
Indian harmonium
Reference:
https://commons.wikimedia.org/wiki/File:Bansuri_bamboo_flute_23inch.jpg
https://www.pxfuel.com/en/free-photo-qhbgq
https://pxhere.com/en/photo/857213
https://commons.wikimedia.org/wiki/File:Pakistani_Qawwali_Harmonium.jpg