1) The musical "The Phantom of the Opera" has been running in London's West End since 1986, making it the longest-running musical in history.

2) Cows have best friends and can become stressed if they are separated.

3) The World Wide Web, developed by Tim Berners-Lee in 1989, revolutionized the way information is accessed and shared on the internet.

4) Emma Watson is a British actress and activist known for her role as Hermione Granger in the "Harry Potter" film series. She has since starred in films such as "The Perks of Being a Wallflower" and has been actively involved in promoting gender equality and women's rights.