Hash rate is a measure of how many hashes miners cumulatively produce per second on the Bitcoin network. A single hash is an attempt to create a Proof-of-Work for a block, and billions of these attempts are made per second by miners around the world. The hash rate indicates how much money, energy, and computing power is being dedicated to processing transactions and securing the network.
Hash rate is also an indication of how much a 51% attack on the network would cost. Since a 51% attack requires a malicious miner to control at least 51% of hash rate, the higher the hash rate, the more prohibitively expensive it is for any miner to launch such an attack.
Bitcoin’s hash rate has been growing rapidly over the past decade as Bitcoin’s price appreciation incentivizes more miners to join the network. Hash rate is influenced by several factors, including Bitcoin’s price, energy prices and available quantities, local weather, and regulatory environments.