In real life there are the bold, the ultra conservative, and everything in between personality types. Poker is no different. There are risks and rewards for each type of play but some styles are definitely proven much more successful than others. Then there are some styles that are plain terrible. It is important to understand which player type you are and how to change styles but it is more essential to know which styles your opponents like to use. This page gives descriptions of the main types of players to better recognize them.

If you can figure out how the others at the table play, you can understand the best way to play them; especially in head to head match ups. There are times to be aggressive and times to lay down your cards. Knowing when, how, and against whom is what you need to learn. If you can remember only one thing, “Don’t be a Donkey” at the poker table.

Donkeys play loose but they aren't necessarily passive or aggressive. They just make bad decisions that often appear random. Statistics mean little to a Donkey. Sometimes they raise when they should fold and other times they call when they should raise. They love to play a lot of hands and they love to chase draws all the way to the river. Donkeys can be found imitating the play of styles such as Fish or Maniacs.
Style of Play: Just Plain Bad
Fish, Pigeon, Calling Station
They tend to play most hands that they are dealt and are willing to overpay pre-flop all the way to the river in hopes of catching a straight or flush. Many times they will make big calls post-flop without a concern for statistics. Most of the time they will leave the raising to other players.
Style of Play: Loose / Passive

Maniac, Bomb
Lots of raises are what you will see when a Maniac or Bomb is at the table. They play very aggressive no matter if they have top pair, low pair, a draw, or just a high card. It is very difficult to read these players because they will play aggressively with just about any two cards. However, you can still be heavily rewarded if you have the nuts because Maniacs will likely make the significant raises for you. They are not afraid to bluff.
Style of Play: Loose / Aggressive
Rock, Mouse,
Nit (very tight)
Some people may tell you that there are specific differences among these types of players. Generally speaking, they are very similar. They are very conservative players that don't play very many hands. The typical hands they won't fold pre-flop tend to be pocket pairs, high suited connectors, and possibly Aces with Jacks or better. One weakness they have is that they can be bluffed out of a pot fairly easily if they do not have the nuts. They tend to suspect that other players have better hands than they actually do.
Style of Play: Tight / Passive
The opposite of a Donkey, a Shark pays a lot of attention to things such as position, the players around him, and statistics. Sharks don't play a lot of hands but they capitalize when they do. Sharks will typically raise pre-flop and they usually play above average hole cards. After the flop, they will usually go for the kill by continuing to raise. If they get a read that another player has a stronger hand, they will fold. What makes a Shark such a good player is that they bet aggressively when they sense weakness, they know when to leave a hand when they are likely beat, and they always keep statistics in mind when making decisions.
Style of Play: Tight / Aggressive