Answer:
Glands are of two principal types:
(1) those of internal secretion, called endocrine, and
(2) those of external secretion, called exocrine.
Some glands such as the pancreas produce both internal and external secretions. Because endocrine glands produce and release hormones directly into the bloodstream without passing through a canal, they are called ductless. For the functions and diseases of endocrine glands, see Endocrine System.
Sweat gland............ ..Sweat
Sebaceous gland... .....Sebum
Lacrimal gland ......... ..Tears
Salivary gland.............Saliva