This example shows you how to make a HTTP request using an Ethernet shield. It returns a Google search for the term “Arduino”. The results of this search are viewable as HTML through your Arduino’s serial window.
The Ethernet shield allows you to connect a WizNet Ethernet controller to the Arduino via the SPI bus. It uses pins 10, 11, 12, and 13 for the SPI connection to the WizNet. Later models of the Ethernet shield also have an SD Card on board. Digital pin 4 is used to control the slave select pin on the SD card.
The shield should be connected to a network with an ethernet cable. You will need to change the network settings in the program to correspond to your network.
In the above image, the Arduino would be stacked below the Ethernet shield.
/* Web client This sketch connects to a website (http://www.google.com) using an Arduino Wiznet Ethernet shield.
For more detail: Web Client using Arduino