Arduino vs Raspberry Pi: which one do you need?

An Arduino is a microcontroller: it runs one program, starts instantly, and is excellent at reading sensors and driving motors with precise timing. A Raspberry Pi is a full Linux computer: it can run a desktop, a web server, Python scripts and even AI models, but it takes time to boot and needs a proper shutdown. Pick an Arduino (or ESP32) for battery-powered gadgets, robots, data loggers and anything that must react in real time. Pick a Raspberry Pi for camera projects, media centres, home servers and anything that needs a screen, networking stack or heavy processing. Many projects use both: the Pi handles the thinking and the network, while an Arduino or Pico handles motors and sensors over a USB or serial link.