How Often Does the Bitcoin Network Difficulty Adjust, and Why Is This Necessary?

The Bitcoin network difficulty adjusts approximately every two weeks, or precisely every 2,016 blocks. This adjustment is necessary to maintain a consistent block interval of roughly 10 minutes.

By adjusting the difficulty based on the time it took to mine the previous 2,016 blocks, the network self-regulates to accommodate changes in the total computational power (hash rate) of the miners.