Most of the time by using 18 decimals. One "Ether" is 10^18 "wei", the smallest unit of currency. Most cryptotokens built on ethereum also use that many units...but not all.
Ah that makes sense - if Bitcoin keeps going at its present rate could 8 units of precision simply not be enough? Would a hard-fork be the solution to this?
If one bitcoin were worth $100 million, then one "satoshi" (the smallest unit in bitcoin) would be worth a buck. So, 8 units of precision is probably plenty.