esp8266
The ESP8266 is a cheap Wi-Fi microchip from Shanghai. I mostly use them as IoT toys.
micropython
Updating firmware:
pip install esptool
esptool.py --port /dev/ttyUSB0 erase_flash
esptool.py --port /dev/ttyUSB0 --baud 460800 write_flash --flash_size=detect 0 esp8266-firmware-vX.Y.Z.bin