Bitcoin Pizza Day, celebrated every year on May 22, commemorates the first known purchase of physical goods using bitcoin. This historic event dates back to 2010, when a programmer named Laszlo Hanyecz made a post on the Bitcoin forum, Bitcointalk. Hanyecz offered 10,000 bitcoins in exchange for two pizzas. 

At the time, the value of 10,000 BTC was approximately 41 USD, meaning each bitcoin was worth just 0.0041 USD. Hanyecz's offer was soon accepted by another Bitcointalk user, who purchased two pizzas for 25 USD, making this the first documented instance of bitcoin being used as a medium of exchange for physical goods. Hanyecz effectively demonstrated the potential of bitcoin as a currency. 

Fast forward to 2018, Hanyecz once again used bitcoin to buy two pizzas, but this time via the Bitcoin Lightning Network, spending only 0.00649 BTC. Despite the staggering rise in bitcoin's value since 2010, Hanyecz has stated in interviews that he has no regrets about his original purchase. Back then, using bitcoin to buy something tangible was a groundbreaking achievement. 

Today, Bitcoin Pizza Day stands as a symbolic reminder of how far cryptocurrency has come. The 10,000 bitcoins used to buy those two pizzas would be worth hundreds of millions of dollars today, highlighting the immense growth and mainstream adoption of bitcoin over the past decade.

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