I2C is a serial bus developed by Philips. They are used in systems that focus on cost over communication speed since networks can be configured with two wires.
They are used in embedded systems, mobile phones, consumer electronics, and other devices.
Further details are beyond the scope of this FAQ but there is a large amount of information on I2C available on the Internet and in other places.
Applicable versions: 01.00.00, 002, and 003