What Is a Raspberry Pi?

A full, tiny Linux computer with GPIO pins — closer to your laptop than to a microcontroller like the Uno, and that difference shapes everything you'll build.

The Arduino Uno section covered a microcontroller: one chip, running one program, with no operating system underneath it. A Raspberry Pi is a different category of device entirely — a complete, general-purpose computer the size of a credit card, running a full Linux operating system, capable of multitasking, connecting to the internet, running a desktop environment, and, alongside all of that, exposing a row of GPIO (general-purpose input/output) pins that let it interact with electronics exactly like the boards you've already used.

That difference shapes what each board is good at. A microcontroller boots your one program instantly and runs it with precise, predictable timing — ideal for a single dedicated job like blinking a light or reading one sensor forever. A Raspberry Pi boots a full OS (taking tens of seconds), can run several programs at once, connects to Wi-Fi and the wider internet natively, and can use a full programming language's entire ecosystem — but its timing on any single GPIO pin is less precise, since the OS is juggling many things at once underneath your code.

In practice, the two are often used together rather than as rivals: a Raspberry Pi might handle the internet connection, a web dashboard, and data logging, while a microcontroller handles the split-second timing of a motor or sensor nearby — the same complementary relationship you'll see reflected across this course.