Instruction cycle facts for kids

The instruction cycle, also known as the fetch-decode-execute cycle, is like a super-fast routine that your computer's brain, the CPU, follows all the time. It's how your computer understands and carries out every single command you give it, from clicking an icon to typing a letter. This cycle has three main steps: fetching, decoding, and executing.

How Does a Computer's Brain Work?

Your computer's central processing unit, or CPU, is like the brain of the computer. It's constantly working to make sure everything runs smoothly. The instruction cycle is the basic operation that the CPU performs over and over again, billions of times per second. It's how the CPU processes all the commands it receives.

Step 1: Fetching Instructions

Imagine your computer's brain (the CPU) needs to do something. First, it has to find out what that "something" is. This is called fetching. The CPU goes to the computer's memory, like a giant library, and picks up the next instruction. Each instruction is a tiny piece of code that tells the CPU what to do next. It's like finding the next step in a recipe.

Step 2: Decoding Instructions

Once the CPU has fetched an instruction, it needs to understand what it means. This step is called decoding. The CPU has a special part that acts like a translator. It figures out what the instruction is asking it to do. For example, is it asking to add two numbers, move some data, or show something on the screen?

Step 3: Executing Instructions

After the instruction is decoded, the CPU then carries out the command. This is the execution step. If the instruction was to add two numbers, the CPU will perform that addition. If it was to save a file, it will manage that process. This is where the actual work gets done.

Repeating the Cycle

Once an instruction is executed, the CPU immediately starts the cycle all over again. It fetches the next instruction, decodes it, and then executes it. This happens incredibly fast, allowing your computer to perform many tasks at once and respond quickly to your commands. It's a continuous loop that keeps your computer running.

See also

• In Spanish: Ciclo de instrucción para niños