Why can't you always have the option to fold a hand?  I see that
sometimes you can fold but other times you can't, i.e., you can check
but not fold.

Also, what is the difference between raising and betting?

Hello skip9801,

It's surprisingly difficult to find a clear answer to your first
question.  So, as a long-time viewer of Texas Hold 'Em programs and
rule explanations, I'll take the liberty of composing my own answer.

In the version that you'll see, for example, on Celebrity Poker
Showdown, two of the players initially post a small blind (half of the
full bet) and a big blind (the full bet).  Before the flop, and in any
round of betting after the flop, every player has the option to fold
rather than bet.  However, before the flop, if no other player raises
the bet, the player who posted the big blind has no reason to fold. 
That player has already posted the full bet.  The other players must
bet to see the flop -- even the player in the small blind must bet
half of the full bet.  But the player in the big blind can see the
flop for free -- in other words, he can check.

In each round after the flop, the first player might not like his
cards, but can still check rather than fold, in the hope that the
other players will check(or, alternatively, will show weakness in
their bets).  If the first player checks, then the second player may
check, and so on until someone bets; all other players must then call
or raise.

For an interactive explanation of the pre-flop procedure, go to the
Celebrity Poker Showdown website
(http://www.bravotv.com/Celebrity_Poker_Showdown/), click "Hold'Em How
To," then "start" on the pop-up window, then "jump to?," and finally
"4. Position and Betting."

A good example of a hand of Texas Hold 'Em is described at:

"Texas hold 'em" [under "Example"
Answers
http://www.answers.com/topic/texas-hold-em

You can find a glossary of poker terms at Pokerpages.com.  It defines
"bet" as "To voluntarily put money or chips into the pot" and "raise"
as "To call and increase the previous bet."  ("Call" means "To match,
rather than raise, the previous bet.")  In other words, betting is
putting money into the pot; raising is increasing the previous bet.

"Poker Glossary - B"
Pokerpages.com
http://www.pokerpages.com/pokerinfo/glossary/glossary-b.htm

"Poker Glossary - R"
Pokerpages.com
http://www.pokerpages.com/pokerinfo/glossary/glossary-r.htm

"Poker Glossary - C"
Pokerpages.com
http://www.pokerpages.com/pokerinfo/glossary/glossary-c.htm

Please let me know if any of this explanation is unclear -- I would be
happy to clarify it.

- justaskscott


Search strategy --

Searched on Google for the following terms, alone or in various combinations:

"celebrity poker"
"texas hold em"
"texas holdem"
poker
glossary
bet
raise

[I tried other searches as well; but the search terms I have mentioned
led me to the pages I have cited.]

Thanks for the great answer.

The easiest way to think of a check is that it's calling a bet of
zero. As to why you may not be allowed to fold when you have the
option to check: it's because it's an almost criminally bad move. If
you can check, that gives you a chance to stay in the game (and
possibly see the next card) for free. To fold offers you no advantage
at all. Beyond that, it's giving away information about your hand,
which could confer an advantage on players in later position, or on a
player with whom you're colluding. So it's no surprise that some
software won't even allow you to make this move.

hobbified's hit the nail. There are some differences between playing
online poker software and a real game. That is, good online software
has built anti-collusion requisites that will not allow such moves.

A good resource for the differences in online and real poker is
http://www.pokerpunt.co.uk/beginners%20guide.htm

we are on the right track here. but in a real game you can (and might
accidentally) fold your hand at any point if the cards are thrown or
mucked into the middle of the table. But as above if you have the
option to check, do it, and you may get to see a "free card". as far
as the difference in betting and raising: if you bet you are the first
person to put money in the pot which normally would be the same amount
as the big blind, or in the second round of betting if you put in the
same amount as the big blind thats a bet. if you want to raise
normally you would need to put twice the big blind in.