The ESP8266 based WiFi module is similar to WiFi Serial Transceiver Module with ESP8266 but it has more pins exposed, making it perfect for prototyping IoT projects. It is an ultra low power UART WiFi device with a small footprint that can process LAN communications and supports synchronous serial communication(SPI).
The 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.
The 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. Its high degree of on-chip integration allows for minimal external circuitry, and the entire solution, including front-end module, is designed to occupy minimal PCB area.