Hardware → Hardware Building Blocks
Arithmetic Logic Unit
The CPU component that performs arithmetic and logical operations.
Motivation
ALU solves the problem of performing arithmetic and logical operations inside a CPU.
Where it fits
ALU belongs to hardware building blocks and is a core part of the CPU datapath.
Mental model
The ALU is the calculator inside the processor: it adds, compares, shifts, and evaluates bitwise logic.
Common mistakes
- Thinking the ALU is the whole CPU.
- Ignoring that control logic decides which ALU operation runs.
Related concepts
ALU connects to CPU, register, instruction set architecture, and logic gates.