While it is saved as a wifi module with a basic serial interface to be controlled from, The ESP8266 actually has a powerful microcontroller that can now easily

While it is saved as a wifi module with a basic serial interface to be controlled from, The ESP8266 actually has a powerful microcontroller that can now easily be programmed using the Arduino IDE (and other stacks). There are different firmwares that allow programming in Lua, Basic, Javascript... or just compile directly from C/C++