1. The identity of Bitcoin's creator, Satoshi Nakamoto, is still unknown.
2. The first Bitcoin transaction involved two pizzas and was worth around $25 in 2010.
3. There will only ever be 21 million Bitcoin in existence, as dictated by the protocol.
4. Bitcoin has experienced multiple price bubbles and crashes, with the most recent one occurring in 2017.
5. The smallest unit of Bitcoin is called a satoshi, and there are 100 million satoshis in one Bitcoin.
6. The total energy consumption of the Bitcoin network is estimated to be around 78 TWh per year, which is more than the entire country of Chile.
7. Bitcoin transactions are irreversible, which means that once a transaction is confirmed, it cannot be reversed or cancelled.
8. The first Bitcoin ATM was installed in Vancouver, Canada, in 2013.
9. The Winklevoss twins, who famously sued Mark Zuckerberg over the creation of Facebook, are now Bitcoin billionaires.
10. Bitcoin is accepted as a form of payment by a growing number of merchants, including Microsoft, Expedia, and Overstock.
11. There have been numerous cases of people losing access to their Bitcoin wallets, including one person who threw away a hard drive with 7,500 Bitcoin on it.
12. Bitcoin is banned in some countries, including China and Morocco.
13. The first Bitcoin conference was held in Prague in 2011.
14. The largest Bitcoin transaction ever made was for 194,993 BTC, worth around $1.1 billion at the time.
15. Bitcoin mining is a competitive industry, with specialized hardware and software required to participate.
16. Some people have had QR codes for their Bitcoin addresses tattooed onto their bodies.
17. Bitcoin's price has been known to be influenced by social media activity, particularly on Twitter.
18. The first ever Bitcoin transaction was from Satoshi Nakamoto to Hal Finney, a well-known cryptographic activist and developer.
19. Bitcoin has inspired the creation of numerous other cryptocurrencies, including Ethereum, Litecoin, and Dogecoin.
20. Bitcoin has been used for some unusual purchases, including a Lamborghini and a private island.