As a term, coins can be used both in online and brick-and-mortar casinos and refers to another type of currency.
Much like casino chips, casinos used to use coins to make everything a tad more convenient. While casino chips were used at table games, coins were used by slot machine players.
However, as technology improved, casinos eliminated the use of metal coins and replaced them with prepaid cards or receipts. Thanks to that, casinos don’t have to deal with jammed machines. Plus, they eliminate the expenses of handling the coins and having to use coin counting windows.
In today’s time, only a handful of land-based casinos uses coins, and the only place where the term is used is among video slot players. Namely, some video slots use the “old way” of calculating your bet, which is represented as a correlation between the number of coins you are betting per line and the amount you are betting.