Complex sentence: The trade fair is held each year on the Hanover fairground, the world's largest fairground, in Hanover, Lower Saxony, Germany, and is considered a barometer of the state of the art in information technology.
Split into simpler sentences: The trade fair is held each year on the Hanover fairground, the world's largest fairground, in Hanover, Lower Saxony, Germany. It is considered a barometer of current trends and a measure of the state of the art in information technology.