What is baldness or hair loss and why? how could grow up hair once again on the scalp?

Hair loss: Male pattern baldness is related to your genes and male sex hormones. It usually follows a pattern of receding hairline and hair thinning on the crown, and is caused by hormones and genetic predisposition. Each strand of hair you have sits in a tiny hole (cavity) in the skin called a follicle. Baldness in general occurs when the hair follicle shrinks over time, resulting in shorter and finer hair.