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Kozosvyst Stas (StasX)
Kozosvyst Stas (StasX)

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🖥️ How Does a PC Work?

A simple breakdown of what’s really happening inside your computer

Computers feel like magic… until you peek inside and realize it’s all logic, electricity, and fast decisions. No mysteries — just clean engineering. Let’s walk through how a PC works from the inside out.


⚡ CPU — the brain that does all the thinking

The Central Processing Unit executes instructions from programs.

Its job is simple but unbelievably fast: add numbers, compare values, move bytes.

The CPU repeats the same cycle billions of times per second:

  • Fetch — get the instruction from memory
  • Decode — understand what it means
  • Execute — perform the action

This loop is the foundation of all computing.


🧠 RAM — short-term memory

RAM stores data the CPU is actively using.

Open a browser → it loads into RAM → CPU processes it.

RAM is extremely fast but temporary — it clears when power is off.


📦 Storage — long-term memory

Your SSD or HDD keeps everything permanent:

  • the operating system
  • apps
  • photos and files

HDD = mechanical, slower

SSD = electronic, fast, silent

When you open a program, its data moves from storage → into RAM.


🖼️ GPU — the artist inside your PC

The Graphics Processing Unit is built for massive parallel work.

It renders:

  • games
  • animations
  • visual effects
  • 3D scenes
  • AI computations

It has its own memory (VRAM) for high-speed graphics processing.


🔌 Motherboard — the communication network

The motherboard connects every component:

CPU ↔ RAM ↔ SSD ↔ GPU ↔ Peripherals

Buses act as data highways.

A wider bus = more data per second.


🔋 PSU — the power source

The Power Supply Unit converts wall power (220V) into stable voltages for the components:

12V, 5V, 3.3V

A high-quality PSU is essential for stability.


🏃 Operating System — the conductor

Windows, Linux, or macOS manages:

  • memory
  • processes
  • hardware drivers
  • files
  • multitasking

The OS is the bridge between people and hardware.


🧩 How everything works together

When you launch an app:

  1. Data loads from SSD
  2. Moves into RAM
  3. CPU executes instructions
  4. GPU renders visuals
  5. OS manages everything
  6. PSU powers the system
  7. Motherboard connects it all

A PC is pure teamwork at electronic speed.


🧵 Final Thoughts

Computers aren’t magic — they’re billions of tiny operations working in perfect sync.

Everything you see on the screen is the result of high-speed logic transforming electricity into digital reality.

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