The human voice consists of sound made by a human being using the vocal folds for talking, singing, laughing, crying, screaming, etc. Human voice is specifically that part of human sound production in which the vocal folds (vocal cords) are the primary noise source. Generally speaking, the voice can be subdivided into three parts; the lungs, the vocal folds, and the articulators. The lung (the pump) must produce adequate airflow to vibrate vocal folds (air is the fuel of the voice). The vocal folds (vocal cords) are the vibrators, neuromuscular units that ‘fine tune' pitch and tone. The articulators (vocal tract consisting of tongue, palate, cheek, lips, etc.) articulate and filter the sound.

The vocal folds, in combination with the articulators, are capable of producing highly intricate arrays of sound. The tone of voice may be modulated to suggest emotions such as anger, surprise, or happiness. Singers use the human voice as an instrument for creating music.

Voice types and the folds (cords) themselves

main: Vocal folds

As seen in the illustration, the folds are located just above the trachea (the windpipe which travels from the lungs). Food and drink do not pass through the cords but instead pass through the esophagus, an unlinked tube. Both tubes are separated by the epiglottis, a "flap" that covers the opening of the trachea while swallowing.

The folds in both sexes are within the larynx. They are attached at the back (side nearest the spinal cord) to the arytenoid cartilages, and at the front (side under the chin) to the thyroid cartilage. They have no outer edge as they blend into the side of the breathing tube (the illustration is out of date and does not show this well) while their inner edges or "margins" are free to vibrate (the hole). They have a three layer construction of an epithelium, vocal ligament, then muscle (vocalis muscle), which can shorten and bulge the folds. They are flat triangular bands and are pearly white in color. Above both sides of the vocal cord is the vestibular fold or false vocal cord, which has a small sac between its two folds (not illustrated).

The difference in vocal folds size between men and women means that they have differently pitched voices. Additionally, genetics also causes variances amongst the same sex, with men and women's singing voices being categorized into types. For example, among men, there are basses, baritones and tenors, and contraltos, mezzo-sopranos and sopranos among women. There are additional categories for operatic voices, see voice type. This is not the only source of difference between male and female voice. Men, generally speaking, have a larger vocal tract, which essentially gives the resultant voice a lower tonal quality. This is mostly independent of the vocal folds themselves.