(**A**rithmetic **L**ogic **U**nit) The high-speed circuit in the CPU that does the calculating and comparing. Numbers are transferred from RAM (memory) into the ALU for calculation, and the results are sent back to RAM. Alphanumeric data are sent from RAM into the ALU for comparing. The results of the compare are tested and may cause the computer to go to another part of the program; for example, **If ItemA equals ItemB GoTo UpdateRoutine**.

**Floating Point Operations**

A division may result in a fraction, and while some ALUs handle floating point operations, which support fractions, others do not and require a separate circuit (see math coprocessor). See DSP.

**Multiple ALUs**

Some chips have multiple ALUs that allow for simultaneous calculations. For example, the Adreno graphics processing unit (GPU) in Samsung's Galaxy S9+ smartphone has 256 ALUs that calculate simultaneously 710 million times per second, resulting in 727 billion floating point operations per second (727 GFLOPS). See computer, control unit and half adder.

**An ALU in 1957**

**Thirty Years Later**

A division may result in a fraction, and while some ALUs handle floating point operations, which support fractions, others do not and require a separate circuit (see math coprocessor). See DSP.

Some chips have multiple ALUs that allow for simultaneous calculations. For example, the Adreno graphics processing unit (GPU) in Samsung's Galaxy S9+ smartphone has 256 ALUs that calculate simultaneously 710 million times per second, resulting in 727 billion floating point operations per second (727 GFLOPS). See computer, control unit and half adder.

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