1) The Brexit process, initiated by the United Kingdom's referendum in 2016, led to the country's withdrawal from the European Union in 2020, marking a significant political and economic change for both the UK and the EU.

2) The name "Bluetooth" comes from the 10th-century Danish king, Harald Bluetooth, who united Denmark and Norway.

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 highest-grossing concert tour of all time is U2's "360° Tour," which earned over $735 million in ticket sales.