The Central Processing Unit (CPU) is often called the brain of a computer. It interprets and executes instructions from both hardware and software. The CPU performs essential tasks such as arithmetic operations, logic decisions, and data processing. It consists of components like the control unit, arithmetic logic unit (ALU), and registers. The speed and efficiency of a computer largely depend on the CPU’s processing power, measured in gigahertz (GHz). Overall, the CPU coordinates all activities within a computer system, ensuring that input is processed, instructions are followed, and output is generated effectively.