There are distinct types of poker players which are categorized based on how they play, and what (cards) they play.
How poker players play is based on whether they are passive or aggressive. What they play is categorized on whether they are tight or loose.
So you can have a poker player that plays with strong starting hands and is therefore ‘tight‘ coupled with an aggressive playing style, which makes that player a tight-aggressive player, or TAG in poker shorthand.
Other types then would be Loose-Aggressive, Loose-Passive, and Tight-Passive. Tight-Passive is the usual style for a player who is trying to clear a poker bonus offer and doesn’t want too much of a swing.
Loose-Aggressive players are called LAG players, but the other types are not given shorthand notations, so there is no TIP or LIP types. I don’t know why that is.
The most difficult type to play against is undoubtedly the Tight-Aggressive player. They will come out shooting and will be holding the best cards more often than not.
Loose-Aggressive players are normally considered to be the weakest type of player and yet TAG players are most vulnerable to LAG players, which is a bit paradoxical.
Before trying to figure out and categorize your opponents you should figure out, firstly, what type of player you are, and secondly, whether you really want to be that type of player.
Tight-Passive players are easy to play against as you can simply fold almost any cards to their bets, except for the top premium hands. And after two or three showdowns where you have the better hand, you can easily bluff them off of medium sized pots.
Loose-Passive players are the worst possible players, in my opinion, as they play too many hands and fold them too easily, thus costing themselves a lot of money with little chance of taking down a pot, except against other loose passive players.
Loose-Aggressive players can be very hard to play against. Even though you know that they are losing players overall they can still put a big dent in your bankroll if you go up against them even with premium hands as they will go to the river with almost anything.
But in the long term Tight-Aggressive players are the hardest to play against, and are going to be the most profitable. Ideally you should try to develop this style of play.
Having chosen your ideal style you now have to learn to switch it up and change styles mid game. Otherwise you will be too easy to read and good players will eat you up. While mastering one style may seem daunting right now, and the realization that you will actually need to develop two or more distinct playing styles may just be enough to put you right off, there is a way out.
Once you have one style down and are confident to play that way for a while, then you can simply change tables and or stakes to avoid getting to well known to the players at your regular tables and stakes. If you feel the need you could open an account at an entirely different poker site. That really is only need if the site you are currently playing at does not have many players, and you find yourself playing against the same old faces (or avatars) regularly.