Hair is primarily composed of a protein called keratin. This fibrous protein is also found in skin and nails. Each strand of hair grows from a root located at the base of a hair follicle, which is made up of keratinized cells.
As hair grows, the keratinized cells from the root migrate upwards, flatten, and die, forming the hair shaft that we see. The hair shaft is essentially a strand of dead keratinized cells.
