Singing is the act of producing musical sounds with the voice and augments regular speech by the use of sustained tonality, rhythm, and a variety of vocal techniques. A person who sings is called a singer or vocalist (in jazz and popular music). Singers perform music (arias, recitatives, songs, etc.) that can be sung with or without accompaniment by musical instruments. Singing is often done in an ensemble of musicians, such as a choir of singers or a band of instrumentalists. Singers may perform as soloists or accompanied by anything from a single instrument (as in art song or some jazz styles) up to a symphony orchestra or big band. Different singing styles include art music such as opera and Chinese opera, Indian music and religious music styles such as gospel, traditional music styles, world music, jazz, blues, gazaland popular music styles such as pop, rock, electronic dance music and filmi (film songs).

Singing can be formal or informal, arranged or improvised. It may be done as a form of religious devotion, as a hobby, as a source of pleasure, comfort or ritual, as part of music education or as a profession. Excellence in singing requires time, dedication, instruction and regular practice. If practice is done on a regular basis then the sounds can become more clear and strong. Professional singers usually build their careers around one specific musical genre, such as classical or rock, although there are singers with crossover success (singing in more than one genre). They typically take voice training provided by voice teachers or vocal coaches throughout their careers.

Voices

In its physical aspect, singing has a well-defined technique that depends on the use of the lungs, which act as an air supply or bellows on the larynx, which acts as a reed or vibrator on the chest, head cavities and skeleton, which have the function of an amplifier, as the tube in a wind instrument; and on the tongue, which together with the palate, teeth, and lips articulate and impose consonants and vowels on the amplified sound. Though these four mechanisms function independently, they are nevertheless coordinated in the establishment of a vocal technique and are made to interact upon one another. During passive breathing, air is inhaled with the diaphragm while exhalation occurs without any effort. Exhalation may be aided by the abdominal, internal intercostal and lower pelvis/pelvic muscles. Inhalation is aided by use of external intercostals, scalenes, and sternocleidomastoid muscles. The pitch is altered with the vocal cords. With the lips closed, this is called humming.

The sound of each individuals singing voice is entirely unique not only because of the actual shape and size of an individuals vocal cords but also due to the size and shape of the rest of that persons body. Humans have vocal folds which can loosen, tighten, or change their thickness, and over which breath can be transferred at varying pressures. The shape of the chest and neck, the position of the tongue, and the tightness of otherwise unrelated muscles can be altered. Any one of these actions results in a change in pitch, volume (loudness), timbre, or tone of the sound produced. Sound also resonates within different parts of the body and an individuals size and bone structure can affect the sound produced by an individual.

Singers can also learn to project sound in certain ways so that it resonates better within their vocal tract. This is known as vocal resonation. Another major influence on vocal sound and production is the function of the larynx which people can manipulate in different ways to produce different sounds. These different kinds of laryngeal function are described as different kinds of vocal registers.The primary method for singers to accomplish this is through the use of the Singers Formant; which has been shown to match particularly well to the most sensitive part of the ears frequency range.

It has also been shown that a more powerful voice may be achieved with a fatter and fluid-like vocal fold mucosa. The more pliable the mucosa, the more efficient the transfer of energy from the airflow to the vocal folds.

Reference Links:  https://en.wikipedia.org/wiki/Singing