What Is the CPU and How Does It Process Instructions

Short answer

The Central Processing Unit is the brain of the computer. It fetches instructions from memory, decodes them, executes operations, and stores results.

How it works

The CPU follows the fetch-decode-execute cycle. It reads an instruction from RAM, interprets what operation to perform, carries it out using arithmetic logic units, and writes the result back.

Example

Adding two numbers involves fetching the add instruction, reading the operands from registers, computing the sum, and storing it in a destination register.

Why it matters

CPU performance defines how fast software runs. Understanding cores, clock speed, and cache helps you write efficient code and choose appropriate hardware.