Hash Power
Hash power measures the volume of cryptographic hashes miners can perform per second in the pursuit of the block reward of a Proof of Work blockchain protocol such as Bitcoin. It’s an important metric because it represents a proxy for how secure the network is.
The more hash power deployed by miners the greater the resources required for a 51% attack to succeed.
This makes Hash Power positively correlated with difficulty level. The more hash power employed in pursuit of block rewards. The higher the difficulty level required to keep block times in sync.
For example, as hash power has been added to Bitcoin’s network the difficulty level has continued to rise to try and keep the block time in sync with the target range of 10 minutes between blocks.