What is the Bitcoin block halving?

Block halving happens every 4 years or 210,000 blocks on the Bitcoin blockchain. The initial rewards for each block found were 50 BTC. Currently they are 6.25 BTC, and next time they will be 3.125 BTC. This causes the frequency of issuing new Bitcoin coins to decrease. This halving is periodic and is programmed into the Bitcoin code.

Why does this exist?

Conventional fiat currencies (FIAT) allow the printing of new money by the government or banks, causing inflation. In the case of Bitcoin, the maximum number of coins that can exist is 21,000,000 BTC. Printing extra money causes inflation. If there is no extra money to be created, the value of Bitcoin should increase as demand will increase (more people will start using Bitcoin) and supply will decrease or stay the same (no more Bitcoins are created). This makes Bitcoin similar to gold, which also has a limited supply and cannot be “printed” or created artificially.