- Pennsylvania (/ˌpɛnsɪlˈveɪniə/; Pennsylvania German: Pennsilfaani), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. Pennsylvania borders Delaware to its southeast, Maryland to its south, West Virginia to its southwest, Ohio to its west, Lake Erie and the Canadian province of Ontario to its northwest, the State of New York to its north, and the Delaware River and New Jersey to its east.
- 20th century (Wikipedia)
The 20th century began on 1 January 1901 (MCMI), and ended on 31 December 2000 (MM). It was the 10th and last century of the 2nd millennium and was marked by new models of scientific understanding, unprecedented scopes of warfare, new modes of communication that would operate at nearly instant speeds, and new forms of art and entertainment. Population growth was also unprecedented, as the century started with around 1.6 billion people, and ended with around 6.2 billion.