A good memory, makes a good player, Memorizing how certain opponents play their favorite hands is paramount in beating them, I know from playing against players I come up against regularly, how they play and what hands they will play.
Some will only raise with A/K or better, others will raise with any 2 suited cards, so being armed with this ammunition I can adjust accordingly and play against them, I have a friend I play against on a regular basis and I know he will raise pre-flop with a wide range of hands because he likes to gamble, he also knows I will only call his raises if I have a premium hand, so he goes on the defensive if I am involved in a hand.
This knowledge for both of us makes for good play and sometimes I use what he believes me to be playing to my advantage, he will continue to bet if he makes 2nd pair on the flop, and I will not call unless I make top pair, so many times I can
bluff if I believe him to be on the 2nd pair, and will immediately raise his continuation bet, this then usually leads to him folding. If he calls then I know he may have better than 2nd pair and then I can slow down, but if I miss the flop completely, I will still play this way because he knows my style of play and will respect my raises 90% of the time.
This makes our
poker games so enjoyable and fun, and if I know the player I will play them and not the cards I am holding. Play the player, Not your hand.
When the fun Stops, STOP!