Bitcoin halving is a process that occurs periodically on the Bitcoin network in order to control the supply of new bitcoins and maintain their value. The Bitcoin network is designed so that new bitcoins are created at a predetermined and gradually decreasing rate. The number of new bitcoins created in each block, which is added to the blockchain approximately every ten minutes, is reduced by half every four years. This is known as "halving" and it is one of the key features of the Bitcoin network.