ESP8266 is a highly integrated chip ,The core processor ESP8266 integrates the industry-leading Tensilica L106 ultra-low-power 32-bit micro MCU in a small package with 16-bit Lite mode, clocked at Supports 80 MHz and 160 MHz, supports RTOS, and integrates Wi-Fi MAC/BB/RF/PA/LNA. 

The ESP-12S WiFi module supports the standard IEEE802.11 b/g/n protocol, a complete TCP/IP protocol stack. Users can use this module to add networking capabilities to existing devices or to build separate network controllers. 

Features：
Size：24*16*3(±0.2)MM 
The smallest 802.11b/g/n Wi-Fi SOC module 
Low power 32-bit CPU, can also serve as the application processor 
Up to 160MHz clock speed 
Built-in 10 bit high precision ADC 
Supports UART/GPIO/IIC/PWM/ADC 
SMD-16 package for easy welding 
Integrated Wi-Fi MAC/BB/RF/PA/LNA 
Support multiple sleep patterns. Deep sleep current as low as 20uA 
UART baud rate up to 4Mbps 
Embedded LWIP protocol stack 
Supports STA/AP/STA + AP operation mode 
Support Smart Config/AirKiss technology 
Supports remote firmware upgrade (FOTA) 
General AT commands can be used quickly 
Support for the two development, integration of windows, Linux development environment