Hashrate = difficulty x time
Hashrate is a measurement of the total combined computational power that is being used to mine and process transactions on a Proof-of-Work blockchain, such as Bitcoin and Ethereum

1000 hashes/second = 1 kh/s

1000 kh/s = 1 Mh/s

1000 Mh/s = 1 Gh/s

1000 Gh/s = 1 Th/s

1000 Th/s = 1 Ph/s

The hash rate of your GPU tells you how many hashes per second it can calculate. If your GPU has a higher hash rate than the difficulty, you’ll find that you have more time to solve each block. If you want to make more money from mining, you want to have a high hash rate.