Ok - I'm gonna try and make it simple - but this is not necessarily a simple topic.

Pot odds = do you have the mathematical odds to make a call.

Implied odds = even if you don't have the mathematical odds to make a call, given your stack sizes and your opp's play will you be able to destack him if you hit with your outs with your mathematically -EV call.

Some people use %s to figure out their pot odds, others use ratios (i.e. 2:1). Either are fine as long as you know how to use them.

There is often confusion regarding how to figure out your pot odds - do I include my money into the final pot to determine my odds or not? I am not going to put the answer in yes or no terms because people think about these things differently. But here is how to figure out your pot odds percentage wise:

You take your bet and divide into what the total pot will be after you call. In the example above it is $2 into a $10 pot. So the pot odds is $2/$12 ($10+$2) = 1/6 or 16.7%.

Ok so now we know how to determine our pot odds - the next battle is knowing how to USE our pot odds.

If that $2 bet is the ONLY call we are going to have to make than all we need is a 1 in 6 (or better) chance to hit out outs by the river for us to make this call.

However, in most cases, you will often face another bet on the turn. This is why I like to determine pot odds on a street by street basis.

In the above example I know I am being given 17% odds and I know I have at least 8 outs (the four Ks and the four 9s). A quick way to determine your odds is multiply your outs by 2 for each street. In this case that means I have about a 16% (or 1 in 6) shot to hit by the turn, and about a 32% (or 1 in 3) shout of hitting by the river.

Because I have about a 1 in 6 shot to hit my turn and I am being given exactly a 1 in 6 odds - I am in essence making an exactly EVEN play by making this call. In other words if the betting were to stop by the turn I would end up making exactly $0 in the long run by making this call. 5 of 6 times I would lose my $2 for a net loss of $10 and 1 of 6 times I would win the pot for a net gain of $10 (10-10=0).

However, in practice, I will make the call here every time (in fact I might even semi-bluff depending on my opp). If I hit my hand, I have a good shot of getting lots of extra value (that's what implied odds are all about), and if I don't I can go through the whole process again on the turn.