This board incorporates an RP2040 microcontroller chip designed by Raspberry Pi is a stateless device, with support for cached execute-in-place from external QSPI memory. Inside the RP2040 is a ‘permanent ROM’ USB UF2 bootloader. For peripherals, there are two I2C controllers, two SPI controllers, and two UARTs that are multiplexed across the GPIO.
Features

Size 50.8mm x 22.8mm x 7mm without headers soldered in

RP2040 32-bit Cortex M0+ dual core running at ~125 MHz @ 3.3V logic and power

264 KB RAM

8 MB SPI FLASHchip for storing files and CircuitPython/MicroPython code storage. No EEPROM

21 x GPIO pins

RGB NeoPixelfor full color indication.

On-boardSTEMMA QT connectorthat lets you quickly connect any Qwiic, STEMMA QT or Grove I2C devices

Both Reset button and Bootloader select button for quick restarts(no unplugging-replugging to relaunch code)

3.3V Power/enable pin

4 mounting holes

12MHz crystal for perfect timing.

3.3V regulator with 500mA peak current output

USB Type C connectorlets you access built-in ROM USB bootloader and serial port debugging

STEMMA QT / Qwiic 4-pin 1mm Pitch White Female Connector Cable 150mm Long – Both Sidecan be purchased seperately.
Resources
Primary Guide: Introducing Adafruit Feather RP2040