There are various types of pimples
Whiteheads - remain under the skin and are very small.
Blackheads - clearly visible, they are black and appear on the surface of the skin. Remember that a blackhead is not caused by dirt. Scrubbing your face vigorously when you see blackheads will not help.
Papules - visible on the surface of the skin. They are small bumps, usually pink.
Pustules - clearly visible on the surface of the skin. They are red at their base and have pus at the top.
Nobules - clearly visible on the surface of the skin. They are large, solid pimples. They are painful and are embedded deep in the skin.
Cysts - clearly visible on the surface of the skin. They are painful, and are filled with pus. Cysts can easily cause scars.