1) The discovery of the Americas by Christopher Columbus in 1492 opened up new trade routes and had a profound impact on world history.

2) The ozone layer, located in the Earth's stratosphere, protects us from harmful ultraviolet (UV) radiation.

3) The Beatles hold the record for the most number-one hits on the Billboard Hot 100 chart, with 20 songs reaching the top spot.

4) The windshield wipers were invented by a woman named Mary Anderson in 1903.