What is a block halving?

A block halving is a process of reducing the rate at which new cryptocurrency units are generated. Specifically, it refers to the periodical halving events that decrease the block rewards provided to miners.

Why are halvings significant?

Halvings are at the core of the cryptocurrency economic models because they ensure coins will be issued at a steady pace, following a predictable decaying rate. Such a controlled rate of monetary inflation is one of the main differences between cryptocurrencies and traditional fiat currencies, which essentially have an infinite supply.

How many Bitcoin halvings have there been previously?

As of July 2019, there have only been two previous Bitcoin halving events. These occurred on the 28th of November, 2012 and the 9th of July, 2016. At the time of the first halving event, the price of Bitcoin was $12.31 and at the time of the second halving event, the price of Bitcoin was $650.63.

There will only ever be 32 bitcoin halving events. Once all of these have occurred, there will be no more halvings and there will also be no more Bitcoin created as the maximum supply will have been reached.