Terahash is the unit used to measure speed of the mining hardware mining cryptocurrencies. It is specified in hashes per second. Where one hash is basically one calculation of the Algorithm. 1 MH/s is One Megahash (Million) hashes per second. One GH/s is billion hashes per second or 1000 Megahashes. 1 TH/s is 1 million Megahashes per second. 1 PH/s is 1000 TH/s and so on.
one hash = 1 hash of the cryptocurrency Algorithm. In our case SHA-256 Algorithm.
Kilohash/s = 1.000 hashes calculated per second.
Megahash = 1.000.000
Gigahash = 1.000.000.000
Terahash = 1.000.000.000.000
Petahash = 1.000.000.000.000.000 A single of our miners mines bitcoins at 4 PH/s.
Exahash = 1.000.000.000.000.000.000
Global total for Bitcoin mining at time of writing is approx. 40 EH/s.