Raspberry Pi Pico is a popular microcontroller (MCU) option for hobbyists and IoT professionals alike. It holds a special place in the IoT world because of its small physical size paired with relatively high processing power and low energy consumption.
Add to that the huge mainstream adoption of its larger siblings (Raspberry Pi 1 through 4) making Raspberry Pi hardware well-known throughout the IoT world. The Pico is also exceptionally cheap, especially compared to the siblings, and you can get started with one in just minutes. You don’t need extensive programming knowledge, and there’s enough documentation online to keep you busy experimenting for weeks on end.