It's The Partial or complete lack of hair resulting from normal aging, endocrine disorder, drug reaction, anticancer medication, or skin disease. Kinds of alopecia include alopecia areata, alopecia totalis and alopecia universalis.
Alopecia Areata
This disease is due to unknown cause in which there are well defined bald patches, usually round or oval, on the head and other hairy parts of body.
Alopecia Totalis
It's the condition characterized by the loss of all the hair on the scalp. The cause is unknown.
Alopecia Universalis
It is characterized by a total loss of hair on all parts of the body, occasionally an extention of alopecia areata.
Dandruff
An excessive amount of scaly material composed of dead, keratinized epithelium shed from the salp that may be a mild form of seborrheic dermatitis.