1) The development of blockchain technology, first introduced in 2008 with the creation of Bitcoin, has enabled secure and decentralized digital transactions and led to the emergence of cryptocurrencies.

2) Angelina Jolie is an American actress, filmmaker, and humanitarian. She has received critical acclaim for her performances in films such as "Girl, Interrupted," "Mr. & Mrs. Smith," and "Maleficent," and has been actively involved in humanitarian work around the world.

3) The Giza Pyramid Complex, situated on the outskirts of Cairo, Egypt, is home to the iconic Great Pyramid of Giza, one of the Seven Wonders of the Ancient World. It was built as a tomb for the pharaohs and represents the pinnacle of ancient Egyptian architecture and engineering.

4) The word "oxygen" contains two vowels: O and E.