George Washington is arguably the most famous of all US presidents. His fame is international, given that he was the first ever president of the country that managed to become the leader of the free world, as well as an economic powerhouse. He served for two terms, from 1789 to 1797, making him the only president to serve two terms in the 18th century (all other US leaders were elected in the subsequent centuries).
He was one of the Founding Fathers of the United States, an important position that set events in motion for hundreds of years afterward (and even today). He served as the Commander-in-Chief of the US Army during the American Revolutionary War, and he presided over the 1787 convention in which the United States Constitution was first drafted.