How many bitcoins will there eventually be? Since bitcoins are being regularly rewarded to miners, will the number of bitcoins continue to grow indefinitely, or will there be a maximum total number of bitcoins in existence?  And if there is some kind of limit, what is it and how is it enforced?
Every block introduces 50 new coins in the system. This quantity (50) halves every 210,000 blocks. So, getting the limit of coins it is possible to generate is quite easy : it's the sum of a geometric series.



Also, note that this is an upper bound ; the actual quantity will probably be a bit lower due to rounding issues (BTC has a finite number of decimals, 8).