What is the difference between limping and an open limp?
I know that when you just pay the bigblind on preflop it's called limping. But what is an open limp?
Open Limp:
When the first player enters the pot by limping in.
Explained
When a player is first to enter the pot and simply limps they are making a call of the big blind. This is generally considered to be a weak-passive play typified by beginning poker players.
Example
The small blind is $5 and the big blind is $10 in a live poker game. The first two players fold. The next player then limps in and calls the big blind for $10. This is an example of an Open Limp.
An open limp is the first one that just pays the bigblind instead of raising.
In most cases it is a weak gameplay because...
... if you've a good hand, you got to protect it and raise instead of just limping. ... if you've a worse hand, your get rid of it and not waste chips for it.
Because it tells everyone on the table that you got a "ok"-hand, not strong, not bad or maybe bad, but obviously not strong.
But in a few cases it makes sense to open limp. Example:
Player A is bigblind with $100.
Everyone beside the button (Player B) and small blind folded.
Player B on botton holds AA (aces) and he knows that if he'd raise both (SB and BB) would fold.
Player B just calls and pays the $100 -> open limp.
Smallblind folds.
Player A checks.
It's risky for someone with a strong hand to open limp or just limp, because he has no clue about the cards of the villian.
Edit:
Another good reason to openlimp/limp with a strong hand is when you are in early position. If you've one or more loose aggressive players behind you, you could just limp in early position and expect that one of the players behind you raise. If this happens you can reraise and build a pretty pot.
Someone who "open limps" is someone who DOESN'T raise with a very strong hand such as AA, but just calls "limps."
He's hoping that someone behind him will raise with a "strong" (but weaker) hand, such as KK, QQ, or AK, so he can re-raise. This is a good tactic if there are a number of people at the table who will raise with a lot of hands, including some that are weaker than these three.
An open limp is when the first person entering the pot (except for the blinds) enters with a limp. A limp is just a call (1 big blind). This is mostly considered a weak play because just calling the big blind implies you have a weak hand. Sometimes it is done in early position hoping one would raise your "weak" hand so you could reraise with a monster (AA, KK).