I never show my cards at the table.

Regardless of if I win, lose - I have auto-muck for all my hands.

I do however see the occasional player showing a card or talking about what cards they have.

To me, this is a bad idea. Some people think there is a strategy to showing as it can tilt someone or setup a future play and whilst this may be true IRL games, online I don't really think this strategy holds, especially at lower levels since most players arent thinking about what you have - they only care what they have.

So lets see what I mean.

You have , you call a large preflop re-raise and the board comes

You are first to act and you bet it, your opponent raises you and you call

Turn comes

You again are first to act, you didn't like the raise so you just check it, you aren't sure your Tens are any good. Your opponent bets it big and you (incorrectly) tell yourself that you have good outs (really you only have 2 more tens and 3 more 2s, so 5 and about 10% chance to improve) and you call the bet

River comes

You are first to act and again you didn't improve so you check, opponent bets it strong and you fold.

You feel like showing and give a glimpse of the as you wanted him to know you had the top pair and (incorrectly) had a good reason to continue on.

 

All you really did was show this guy that all he has to do is bet at you strong and he can push you off top pair or that if you have top pair you will stay in the hand until (almost) the bitter end.

What did your opponent have? - you have no idea because he is smart enough not to show you his cards!

 

I would never ever ever recommend showing your cards or saying "oh, i folded the quads" - you folded, at that point your hand can't win and giving free information just lets other people know something about you.

Will that something always help them? probably not - but it can't really help you!