ProgramViz
Step 220–25 minutes

CPU Basics

The Central Processing Unit (CPU) is the "brain" of the computer. Its job is to fetch instructions from memory and carry them out.

Inside the CPU, three main components work together to make this happen:

Inside the CPU

Control Unit (CU)

The "Manager". It decodes instructions and coordinates how data moves around the computer.

Arithmetic Logic Unit (ALU)

The "Calculator". It performs all the math (addition, subtraction) and logic (AND, OR, NOT).

Registers

The "Scratchpad". Tiny, ultra-fast storage locations inside the CPU for immediate data.

Program Counter
Instruction Register
Accumulator
General Purpose

Registers You Should Know

Program Counter (PC)

Stores the memory address of the next instruction to be executed.

Instruction Register (IR)

Stores the current instruction being processed.

What Is a Program?