A Processor or GPU's embedded device that handles math and reasoning tasks is known as an ALU. While logic instructions use logical evaluations like AND, OR, XOR, and NOT operations, arithmetic instructions use addition, subtraction, and moving operations.

For performing integer computations, ALUs are made. As a consequence, in addition to adding and removing numbers, ALUs are frequently used to multiply two integers because the outcome is also an integer. However, since the output could be a percentage or a "floating point" integer, ALUs usually do not execute division calculations. Instead, the floating-point unit (FPU), which also handles other non-integer computations, typically handles division tasks.

Although the ALU is a basic part of all CPUs, various processor types may have distinct ALU designs and functions. For instance, while some ALUs are only capable of performing integer computations, others are also built to manage floating point functions. While some CPUs only have one arithmetic logic unit (ALU), others have multiple ALUs that collaborate to execute computations. An ALU's main function, regardless of how it is constructed, is to manage number computations. As a result, the ALU's working efficiency directly affects a computer's numerical performance.