The ESP8266 is a low-cost Wi-Fi microcontroller, with built-in TCP/IP networking software, and microcontroller capability [ESP8266 (Wikipedia)]]

Setup board manager

To use the ESP8266 board, you need to configure the board manager. To do this, in the Arduino IDE environment, select preferences and in the Additional URLs field, enter the URL http://arduino.esp8266.com/stable/package_esp8266com_index.json.

OTA (Over The Air updates)

After trying everything, it’s time for the final installation, but sooner or later you’ll have to update the program that’s been loaded into the microcontroller. Disconnecting it, connecting it to the computer, reconnecting all the cables, etc. can be a real nightmare. What’s the solution? OTA (Over The Air) wireless updates.