NU ABO (NU 예삐오) is the first mini album by f(x). It was released on May 4, 2010 with "Nu ABO" serving as the album's title track. "Mr. Boogie" was used as a follow-up track during promotions.
The title of "NU ABO" is a word play meaning "new blood type", A, B and O being blood types. This is implying that they are "new blood" to the K-pop world.