Here is Wikipedia's definition of Texas Hold'em also known as the "Cadillac of Poker":
"Texas hold 'em (also known as hold'em or holdem) is a variation of the standard card game of poker. The game consists of two cards being dealt face down to each player and then five community cards being placed face-up by the dealer—a series of three ("the flop") then two additional single cards ("the turn" and "the river"), with players having the option to check, bet, raise or fold after each deal, i.e. betting may occur prior to the flop, "on the flop", "on the turn", and "on the river"."
With a pre-flop bet, a bet after the flop, a bet after the turn and a bet after the river there are a lot of opportunities to get money in the pot, scare your opponent away, or throw your money away at a bad hand. There are two types of limit games (limit meaning your raise is limited), fixed limit and pot limit, while there are others they ave variations of these two. Fixed limit means you may only bet up to a specific amount, usually twice the size of the blind (blinds will be explained in my next article). Pot limit you may bet up to the total amount which has already been bet, meaning if the amount in already in the pot is 5,000 chips, you may bet up to 5000 chips; this would now make 10,000 in the pot, so the next player may raise up too 10,000 chips. I will get more in depth into re-raising limits and betting later on. No-limit is self explanatory, bet however much you would like at anytime.