1) The Age of Exploration, during the 15th and 16th centuries, saw European explorers such as Christopher Columbus and Vasco da Gama reach new lands and establish trade routes.

2) The fastest recorded serve in tennis was achieved by Sam Groth at 163.7 miles per hour (263.4 kilometers per hour) during a tournament in 2012.

3) In Chinese mythology, the Dragon Boat Festival (also known as Duanwu Festival) is celebrated to honor Qu Yuan, a poet and statesman of ancient China. It involves dragon boat races, eating sticky rice dumplings (zongzi), and performing rituals to ward off evil spirits and protect against diseases.

4) The European Union (EU) is a supranational organization comprising 27 member states that cooperate on various issues, including trade, economic integration, and common policies, while preserving individual national sovereignty.