Two acids, two completely different jobs
AHA stands for alpha hydroxy acid. BHA stands for beta hydroxy acid. Both are chemical exfoliants, but they work on different layers of skin and target different problems. AHA is water-soluble. It works on the surface, dissolving the bonds that hold dead skin cells together so they shed. BHA is oil-soluble. It goes past the surface and into the pore itself, cutting through sebum to clear blockages from the inside.