A wind instrument is a family of instruments that is defined by their characteristic of vibrating a column of air in order to create a sound. The woodwind family is quite large and is divided into two main sections: the woodwinds and the brass instruments. Both of these sections are defined below along with their respective instruments.
The pitch of a wind instrument is almost entirely determined by the frequency at which the wave inside the instrument is vibrating. There will be a high frequency for a high pitch and a low frequency for a low pitch. How loud the instrument is playing, on the other hand, is not at all determined by the frequency at which the instrument is vibrating however, it is determined by how large the waves are in amplitude. The larger the amplitude of a wind instrument, the louder it will be heard by humans. The way sound is created is when a column of air is blown into the instrument, it creates a pitch that is loudest when the column is longest. The frequency of the wave can be determined by the times it takes the column of air to reach the end of the tube and then for that same wave to return to its original position. As the player of the instrument close and opens holes in the tube, the length of the tube will vary thus the frequency and pitch will also vary. This idea also makes sense in the fact that the larger a wind instrument is, the lower notes it can play