Lets look at how a round of betting goes:
Youre the first to act in a game with antes. There are two things you can do:
check (pass the bet) or you can
bet. Lets say you bet.
The next player (the one sitting on your left) can do three things: she can
call or see your bet, which means she matches it exactly; she can
raise the bet; or she can give up on her hand and
fold or "
muck" it.
This continues from player to player going around to the left. If someone raises a bet you made, when it comes back to you, you have the same options as everyone else: call, raise, or fold. The round of betting is over when everyone simply calls the last bet and all the players (who havent folded) have put in the same amount of money. A round of betting can also be checked around meaning everyone checks and theres no money put in the pot that round.