The hashrate is divided into one unit per thousand. The smallest one is Hash/s, standing for one time per second.
1Thash/s=1000Ghash/s； 1Phash/s=1000Thash/s； 1Ehash/s=1000Phash/s.
Hash/s can also refer to as H/s
Besides, due to the different algorithms, Zcash (ZEC) and some other coins use a different hashrate unit name called “sol/s”, but it is essentially no differences, and it equals H/s.