Both cause circular growths or lumps on the skin and can look similar. A boil looks like a large pimple ... an abscess—an enclosed pocket of pus and dead tissue—forms. In contrast, cysts ...

that looks like a cyst, boil, or deep pimple. As these bumps or nodules grow, they join together and fill up with fluid, becoming abscesses. When the mass breaks open, blood and pus is expelled.