Beta hydroxy acid
A beta hydroxy acid (BHA) is an organic compound which contains a carboxylic acid functional group and hydroxy functional group separated by two carbon atoms. They are closely related to alpha hydroxy acids, in which the two functional groups are separated by one carbon atom.
In cosmetics, the term beta hydoxy acid generally refers specifically to salicylic acid, which is used in some "anti-aging" creams.
Other beta hydroxy acids include: