I don't know who needs to hear this but:

-Kilohash per second: 1,000 hashes per second

-Megahash per second: 1 million hashes per second (typically a single GPU or CPU).

-Gigahash per second: 1 billion hashes per second (mining pool or cluster of GPUs).

-Terahash per second: 1 trillion hashes per second (typically a single ASIC or large mining pool).

-Petahash per second: 1 quadrillion hashes per second (large mining pool).

-Exahash per second: 1 quintillion hashes per second (typically a huge mining pool or entire network).

-Zettahash per second: 1 sextillion hashes per second (soon).

GM☕