The ESP8266 is capable of either hosting an application or offloading all Wi-Fi networking functions from another application processor. Each ESP8266 module comes pre-programmed with an AT command set firmware, meaning, you can simply hook this up to your Arduino device and get about as much WiFi-ability as a WiFi Shield offers (and that’s just out of the box)!
ESP8266 2mm Pitch 40 Pin Female Header FEMALE HEADER SOCKET 12 PIN 1×12 FEMALE RECEPTACLE 2mm 079″ Pin Spacing Single Row Straight Mates with 0 5mm Square Post 2 0mm Centerline Headers