ESP8266 is a highly integrated chip designed for the needs of a new connected world. It offers a complete and self-contained Wi-Fi networking solution, allowing it to either host the application or to offload all Wi-Fi networking functions from another application processor. Full I/O port and Wireless 802.11 supported, direct download no need to reset Arduino compatible, works great with the latest Arduino Firmware link: https://github.com/nodemcu/nodemcu-firmware ESP8266 has powerful on-board processing and storage capabilities that allow it to be integrated with the sensors and other application specific devices through its GPIOs with minimal development up-front and minimal loading during runtime.