Everyone knows this: You are sitting at a table with one or more very aggressive poker players. You raise and the other player keeps raising. How do you defend yourself against such aggressive poker players?
First, you should consider whether you caused this by raising too often with weak hands, or whether you simply limped too often (i.e., called before the flop instead of raising). The aggressive player will notice this especially online, where many players use software that collects data on other players.
A quick explanation: A raise on a first raise is called a 3bet, any other raise on the same street is called a 4bet, 5bet, etc. Aggressive players can be identified by the fact that they 3bet relatively frequently. They target players who make a lot of raises with relatively weak hands. They rely on the fact that these weak hands are often still weak after the flop and try to get the other player to fold with an aggressive bet after the flop.
Aggressive or manic opponent?

You need to pay close attention over time to how often players 3- and 4-bet and from what position they do so. Those who do it too often and from a bad position are often maniacs – these players are not impressed with 4bets. Here you should hold the small pot preflop and then bet postflop when you have a hand.
Good aggressive players pay attention to their position and play selectively aggressively against opponents they have identified as weak and in situations where neither player has signaled a strong hand.
The best way to deal with these opponents is to only raise with hands where you are willing to make a relatively large 4-bet after an opponent 3-bets. Of course, premium hands like AK, AQ and top pair through TT are best for this. However, it doesn’t matter what you have yourself. It’s more about showing your opponent that you are not easy to fold and that you know how to deal with aggressive play.
Often, just doing it once or twice is enough to show your opponent your teeth. This way, you create an image at the table and your opponents respect you more. You may lose here and there, but in the long run, an aggressive board image is beneficial, especially if you have a strong hand at one point. There is no need to slow down, as your opponents are more likely to call you with weaker hands since they are more likely to bluff.
Slow play

Both maniacs and good aggressive players are prone to slow play. If you play a very strong hand slowly, they will often try to bluff you out of it. However, if you then call such a bluff bet, good players often notice and refrain from betting any further. They think about what the other person might have, and in such situations it helps to have good plans on the table.
Even if you do have a monster, you can play the hand in such a way that your opponent thinks you’re pushing. These hands can be very profitable: you’ll often get called on the river even after you’ve gone all-in, because your opponent suspects a desperate bluff after a failed draw and has reason to believe that your middle pair is still good.