Certain cards call for using counters; these are tokens used to track numbers. This set includes counters for use with the base game and the first two expansions. If you need more counters, you can substitute anything suitable, such as glass stones, poker chips, or coins. Also, some cards require you to place counters in a particular area. When you use those cards, designate a part of your play are for those counters.
The 1- and 5-point counters are for use as both Succession and Coin counters, and you can use them for other things as needed. Be sure to keep these in their proper areas to avoid confusion.