Bitcoin Pizza Day is celebrated every May 22, commemorating the historic transaction in 2010 when Laszlo Hanyecz bought two Papa John's pizzas for 10,000 BTC.
Laszlo offered Bitcoin on the BitcoinTalk forum to order pizza, and Jeremy Sturdivant sent it after receiving the BTC.
At that time, 10,000 BTC was worth only about $41.
This transaction became the first proof that Bitcoin could be used for real purchases, marking the initial step towards the adoption of digital currency.