Quick Answer: A Raspberry Pi is a small, low-cost single-board computer that runs a full operating system such as Raspberry Pi OS. Processor, memory, USB, networking and a 40-pin GPIO header sit on one board. You add a power supply, a microSD card and a display. As of October 2026 Raspberry Pi describes the Zero 2 W as a $15 computer and lists the Raspberry Pi 5 from $45.
It is a real computer, not a toy. This guide covers what the board does, which model families exist and what else you need. To compare boards one by one, see our Raspberry Pi model comparison.
What is a Raspberry Pi, in plain terms?
It is a credit-card-sized computer made by Raspberry Pi. The Raspberry Pi 5 shows what is on one board: according to the official Raspberry Pi 5 page, checked in October 2026, a 2.4GHz quad-core 64-bit Arm Cortex-A76 CPU, 1GB to 16GB of RAM, two USB 3.0 ports, two USB 2.0 ports, Gigabit Ethernet, dual-band Wi-Fi, Bluetooth 5.0, dual 4Kp60 HDMI output and a standard 40-pin GPIO header.
GPIO stands for general-purpose input/output. Those pins let the board talk to buttons, sensors, LEDs and add-on boards. Our GPIO pinout guide shows what each pin does.
What can you use a Raspberry Pi for?
Most people use one for a small always-on job or a learning project. The common uses:
- Desktop computer. The recommended Raspberry Pi OS edition is a desktop with basic software.
- Home server. File sharing and network storage run on a Pi. See our Docker guide for one route.
- Smart home hub. Home Assistant runs on a Pi 4 or Pi 5. Steps are in our install guide.
- Retro games console. Emulation systems target the Pi. You need legally owned copies of any games you play.
- Sensors and electronics. Start with our sensors guide.
Which Raspberry Pi model families exist?
Five families are worth knowing. The table uses Raspberry Pi's product list, checked in October 2026. Many products show no price there, and prices change.
| Family | Example | What it is for | Price shown (October 2026) |
|---|---|---|---|
| General-purpose board | Raspberry Pi 5 | Desktop, server, projects | From $45 |
| Tiny board | Raspberry Pi Zero 2 W | Small, low-power builds | Described as a $15 computer |
| Keyboard computer | Raspberry Pi 500 | Complete desktop in a keyboard | $180 |
| Embedded module | Compute Module 5 | Products and custom hardware | From $67.50 |
| Microcontroller | Raspberry Pi Pico 2 | Single-task electronics, no desktop OS | From $5 |
Source: raspberrypi.com/products. Older boards such as the Pi 4 Model B and Pi 3 are still listed, without a price. The Pico is a different kind of device. Raspberry Pi describes it as a microcontroller board, built for single-purpose programs and not for running a desktop, which is why it sits in its own row.
What do you need besides the board?
You need four things. Raspberry Pi's getting started documentation, checked in October 2026, recommends an official power supply suited to your model, and a microSD card of at least 32GB for the desktop OS or 8GB for the Lite OS. You also need a display and a keyboard and mouse, or a second computer to reach the Pi remotely.
- Power supply. The Pi 5 is specified for 5V/5A over USB-C. Read our power requirements guide before you reuse a phone charger.
- microSD card. The board has no built-in storage, so the operating system lives here.
- Display and cable. Boards differ. The Zero 2 W uses a mini HDMI port.
- Keyboard and mouse. Or skip them and work over the network.
What are the first steps?
Write an operating system to the card with Raspberry Pi Imager, then boot. Imager is Raspberry Pi's free tool for writing an OS to a microSD card, and it runs on Windows, macOS and Linux. Raspberry Pi OS is the official operating system. As of October 2026 the latest version is based on Debian Trixie, per the Raspberry Pi OS documentation.
- Install Imager on your computer and open it.
- Pick your Raspberry Pi model, then the operating system, then the card.
- When Imager offers customisation, set a hostname, your own username and password, and your Wi-Fi details. The documentation lists these options. Choose your own password and do not reuse one from another account.
- Write the card, put it in the Pi and connect the power.
For other systems, see our guide to operating systems for the Pi. If a board is already on your desk and you cannot tell which one, here is how to identify the model.
When is a Raspberry Pi the wrong choice?
When you need a machine that runs Windows programs, or one with more performance than a small Arm board gives you. A Pi runs Linux on an Arm processor, so software written for Windows will not simply run on it. For one fixed, repeated task with no operating system, such as reading one sensor, a Pico-class microcontroller is the better fit, and Raspberry Pi lists the Pico 2 from $5 as of October 2026. Never use a Pi to switch mains-powered equipment directly. That is a job for certified products, and for a licensed electrician where wiring is involved.
Frequently asked questions
What is a Raspberry Pi used for?
People use it as a desktop computer, a home server, a smart home hub, a retro games machine and a base for electronics projects.
Is a Raspberry Pi a full computer?
Yes. It has a processor, memory, storage through a microSD card, networking and video output, and it runs an operating system. The recommended Raspberry Pi OS edition is a desktop, so you can use it like a small PC.
What are some Raspberry Pi ideas for beginners?
Start with a desktop setup on Raspberry Pi OS, then try a small sensor project on the GPIO pins or a home server.
What are the applications of Raspberry Pi?
They include education, home automation, file servers, retro gaming, cameras, sensor logging and prototypes. Compute Modules exist for people building their own hardware.
What are the functions of a Raspberry Pi?
It computes, connects to networks, plays video and audio, and controls external electronics through its GPIO pins. The software you install decides which you use.
Does a Raspberry Pi come with an operating system?
The board has no built-in storage, so you write an operating system to a microSD card yourself with Raspberry Pi Imager. Check the product listing if a bundle says the card is already prepared.
How much does a Raspberry Pi cost?
As of October 2026 the products page lists the Raspberry Pi 5 from $45 and describes the Zero 2 W as a $15 computer. Add a power supply, card and display. Prices move, so check the official page before you buy.