ALU, alu or Alu may refer to:

Computing

• Arithmetic logic unit, a digital electronic circuit that performs arithmetic and bitwise logical operations

Life science

• Alu sequence, a short stretch of DNA originally characterized by the action of the Alu restriction endonuclease
• Arthrobacter luteus, a gram stain positive bacteria

In Akkadian and Sumerian mythology, Alû is a vengeful spirit of the Utukku that goes down to the underworld Kur. The demon has no mouth, lips or ears. It roams at night and terrifies people while they sleep, and possession by Alû results in unconsciousness and coma; in this manner it resembles creatures such as the mara, and incubus, which are invoked to explain sleep paralysis. In Akkadian and Sumerian mythology, it is associated with other demons like Gallu and Lilu.