Sebaceous glands are important parts of the skin. (The skin is also known as the "integument", or "integumentary system".
Sebaceous glands are glands, i.e. groups of cells specialized for synthesizing and secreting specific fluids, that synthesize an oily substance called sebum. The sebum is then released to the surface of the skin. These are exocrine glands (rather than endocrine glands) because they discharge the sebum via ducts rather than directly into the bloodstream.
To view the location of sebaceous glands relative to other parts of the skin see the diagram of the structure of the skin. This may be of particular interest to students of courses in massage, reflexology, beauty therapies, and other health science or clinical courses.