Whitehead
When skin oil and debris are trapped in the skin pores, they can form into white, raised bump known as whitehead. Whitehead is also called a closed comedo because the plug stays beneath the skin surface.Blackhead
Blackhead is a pinhead-sized dark spot on the skin caused by small plug in skin pore. In contrast to whitehead, the plug of a blackhead enlarges and opens up the pore, reaching the surface of the skin. Blackhead is also known as open comedo. You can't wash blackhead away because the black spot isn't trapped dirt. It is actually the dark pigment of your skin, couple with the oxidized skin oil after exposing to the air.Papule
When a pimple bursts under the skin, it turns into a papule infecting the surrounding tissue. A papule looks like a small pink dome and is tender to the touch.Pustule
A pustule is a papule deeper under the skin, swollen and filled with pus. It appears small on the skin surface with a whitish or yellowish cap in its center and may be red at the base. Pustule may occur anywhere on the body, but is usually seen on the face, shoulders, back, and over the breastbone.Nodule
Nodule is huge, painful and solid. It starts out as a bump filled with blood that is later filled with pus. Nodule can be so sore to your touch you don't want to squeeze it at all. It can stay deep within the skin for months and eventually leave you with a deep scar.Cyst
A cyst is a closed pocket or pouch of tissue. Cyst is common on the skin and may develop as a result of harden nodule. It is a firm swellings beneath the skin surface that become inflamed from a severe case of acne. Cyst is deep, painful, and pus-filled and can cause scarring.People with acne typically develop a assortment of lesions. Whitehead and blackhead are two common forms of acne lesions of the type called comedones. Though they aren't sore, they may stay in the skin for a long time. Other troublesome acne lesions include papule, pustule, nodule and cyst. They are painful to the touch and usually pus-filled because of bacteria infection. Knowing the different types of acne lesions will help in your search of appropriate treatment.