Blackheads are pimples that are located mainly on the face. It is caused by a build-up of sebum in a pore of the skin. Blackheads are generally found on the nose, but can appear on other parts of the body. Acne is characterized by the proliferation of blackheads, which are sometimes infected. The appearance of blackheads can be limited by careful and regular cleaning of the skin. In cases of acne, it is generally recommended not to touch the blackheads and not to pop them. Some products such as benzoyl peroxide or retinoids can reduce blackheads.