Arduino WiFi Shield 101
Arduino has discontinued this shield, please check out the Adafruit WINC1500 shield for a nearly-identical replacement with the same exact module, and the addition of a micro SD card holder and prototyping area.
Arduino WiFi Shield 101 is the new IoT enabler shield based on the ATWINC1500 module, developed with ATMEL, that connects your Arduino to the internet wirelessly!
Connecting it to a WiFi network is simple, no further configuration in addition to the SSID and the password are required. The WiFi Shield 101 comes with an easy-to-use library that allow to connect you Arduino board to internet with few instructions. The WiFi Shield 101 also features a complete asymmetric (public/private) hardware key cryptographic signature solution that is an ultra secure method to provide key agreement for encryption/decryption, specifically designed for the IoT market.
As always with Arduino, every element of the platform – hardware, software and documentation – are freely available and open-source. This means you can learn exactly how it's made and use its design as the starting point for your own projects.
Note: The Wifi Shield 101 is fully compatible and designed for use with Arduino Zero board. The shield has a basic compatibility with Arduino Uno but is under heavy development, using it now could have some minor issues. We're pretty sure it won't work with the Arduino Leonardo or other 32u4 based boards because the code size is a bit high. Find here more information about the Arduino WiFi Shield 101.