Last time I talked about what makes a good table. Today I'll talk a bit about the different individual personalities you'll encounter. A majority of players can be classified along two dimensions: loose vs. tight & passive vs. aggressive.
Loose vs. Tight
This dimension is primarily about what cards a player is willing to play. Loose players tend to see a flop with a much wider range of hands than tight players. At the extreme, a loose player could be playing with any two cards. Tight players, on the other hand, have much more restrictive calling standards. Some loose players also like to make “loose calls”, which mean they'll call down bets when they have a drawing hand, trying to get lucky, when the odds don't justify it.
Passive vs. Aggressive
This dimension is primarily about how a player bets their hands. Passive players tend to check/call their good hands, while aggressive players tend to bet/raise. When you are just calling other people's bets, you only give yourself one way to win: you have to show down the best hand at the end. When you bet or raise, you give yourself two ways to win: either your opponents will fold, or you'll show down the best hand at the end. Also, aggressive players tend to get more money into the pot.
Loose/Passive
This is my favorite kind of player. Since they play such a wide range of hands compared to me, I usually have a mathematical advantage when we're in a pot together. They also like to call bets, but rarely raise, so it's not very expensive if I misread their hand. The best tactic to use is to simply bet heavily with any good or marginal hand. You can expect to be called by a much weaker hand. If they do make that rare raise, you can be confident that they probably have a very good hand. These players are usually all long term losers.
Tight/Passive
These players are usually pretty easy to play against, but tough to win much money from. They have good calling standards, so you can expect them to have a decent hand when you're up against them. But they're always afraid of a better hand, so it's tough to get them to call your bets when you're ahead. Luckily, that fear also prevents them from betting or raising much when you're behind, so it's not that expensive if you make a misread. The best tactics are to bluff much more frequently against them, but be wary if they call those bets. And frequently, on the river, you'll be faced with a decision of whether or not to bet your marginal hands. Since they will only call your bet if they can beat you, it's sometimes more profitable to just check down those hands. These players usually manage to make a tiny profit.
Loose/Aggressive
These players can be really tough to read. They play a wide range of hands and are constantly betting & raising with them. It can be expensive if you make a misread. Since they bluff so often, they get a ton of callers when they make their monster hands and can win some huge pots. But most of the time they don't have anything at all. Some good tactics are to check your good hands, let them bet, then raise it. If they put in the first bet, you almost always want to raise it if you have a good hand. These players either win big or lose big, depending on their luck. Most are long term losers, although some expert players can make a profit using this style, but that's usually at no-limit.
Tight/Aggressive
These are the most dangerous players to play against. They have high calling standards and bet/raise frequently. It can be expensive if you misread them, but luckily they're easier to read than the loose/aggressives. If they're in a hand with you, they more than likely have something. If you see them raise, or check-raise, they more than likely have a strong hand. They are very capable of bluffing though, especially if you appear weak. There are no simple tactics you can employ against them, except to avoid them if at all possible. This is the style that most professionals use and they are usually long term winners.