Let's start with the fact that there are two ways of winning a hand. The first of course is to show down the best hand. We'll call this hand equity. The second is to win by having everyone fold. We'll call this fold equity.

We'll also bet or raise our hands based upon these two principles. When we are betting due to hand equity, where we probably have the best hand, we aren't bluffing. On the other hand, anytime we don't have such an advantage, and we bet or raise, this would involve a bluff to a certain degree, since we are looking to take advantage of fold equity.

Bluffs are generally divided into two different categories. Cold bluffing involves no real chance to win the hand, where the player is looking to take advantage of fold equity pretty much completely. In other words, the only realistic chance they have to win is if they take the pot down by everyone folding. The second category is called semi-bluffing, which involves both the chance of opponents folding and the chance that the player may hit his hand and win that way as well. An example of this would be betting a flush draw, where you could win it now by your opponent or opponents folding, or if you get called, you could complete your flush and win the hand that way.

However, if we are going to be serious about our examination into this, it's better not to have these categorized in such a black and white fashion. There's almost always going to be some chance of winning with cold bluffs, and bluffs are going to vary by degree both in regard to the chances of taking the pot down and the chance of hitting the best hand. So, instead, we'll look at both these factors, and add them up to try to determine what our chances of winning the hand are, and whether a bluff would be a profitable move or not.

Before we get into that, let's take a brief look again at why we want to bet. As a general rule, any time we have the advantage in a hand we're going to want to increase the size of the pot, which will in turn increase our equity - our net profit with the hand on average. And occasionally, we may be on a draw and have the advantage - for instance, on a straight flush draw. So we'll define advantage here as being more likely than not to win the hand. Since we have this advantage, fold equity isn't something we want to take advantage of - on the contrary, we want players to stay in the hand when this is the case, because we are the favorite to win it, and thus we'll derive the most profit in the long run by this.

Any other time we bet, or consider betting, we'll term it a bluff of some sort. Now there may be instances where we have the advantage in terms of pot odds - for instance, with 3 people in the pot and a 40% chance of winning, but any time that our chances of winning is below 50%, fold equity may be to our benefit, thus we want to account for it in our decision making.

So the first step is going to be to try to figure out as best we can what our chances of winning the hand outright will be. There are two situations where we'll find ourselves in when attempting to calculate this. One is with cards to come, and the other is at the river where the cards have been dealt. At the river it becomes simpler in a sense, since we're not needing to figure out outs or draws anymore. All the cards have already been dealt. We're going to have to guess here in a sense, but it will be an educated guess based upon the play of the hand in reference to the typical play of the opponent. Through experience, we'll get better and better at being more accurate with these guesses.

The second is when there are cards to come, and we're going to have to figure out our chances of winning by hitting our hands. We will be doing this anyway though since it is necessary anytime we are on a draw. This does become a little trickier though, since we need to calculate the advantage of betting rather than checking or raising instead of calling in terms of our odds of winning.

This differs from calculating overall odds in a very important way though. Any time we're looking to contribute extra money to the pot, we're going to need not only odds on the overall pot, but odds on the additional money as well. For instance, assume that the odds of staying in the hand are favorable for your draw. You're down to one opponent though, and he checks to you. You're going to have to be a 50% favorite or more to want to bet this based on hand equity alone, because you're only getting 1:1 odds on this additional contribution. This fact is misunderstood badly by most players and it extends to draws in general, not just considering if to bluff or not.

So, regardless of the situation, we have our estimate of our chances of winning the hand outright, whether there be cards to come or not. The other part of the equation is of course calculating our chances of winning without showing down. This will require we have a fairly good read of our opponents of course, otherwise we are shooting in the dark, and that usually ends up costing us money.

What we're going to need here, based upon our observations, is the chances of our bet or raise being successful in taking the pot down. A general idea will do, however, we need to be careful to have fairly good information to work with, so we're just not taking a wild guess. These things can get pretty complicated, but for now we're just looking for a rule of thumb we can use.

Here's the important thing. We need to assume that, of the hands our opponents will fold, thsy will be folding the worst ones and playing the better ones. For example, if we have a 1 in 3 chance of winning, and the opponent will foild 1 time in 3 in this situation, we need to assume it is the third where we best them that they will be folding. In this case, it would not be wise to bet, since it would represent no advantage. However, what if the chances of him folding were greater than 1 in 3? That's a different story.

The advantage of fold equity generally is the difference between the percentage of hands we'll win by bluffing versus the percentage we'll win purely on the strength of our hand. In these cases, we're causing our opponents to lay down better hands, which is a good thing generally of course. And in a nutshell, this is what bluffing is all about, although there are other considerations here such as money odds which is going to make this more complicated of course.

At this stage though, we're looking for a simpler rule of thumb, one that is going to be true generally and can be applied easily without needing a lot of experience and feel for our chances. And it's better to err a bit on the side of caution anyway. Later on, in more advanced lessons, we can delve into the math of the thing more to get us in a few more situations, and also look at other considerations of bluffing such as getting free cards.

So here it is. Since, by definition, we have less than a 50% chance of winning when we're bluffing, any time it's more likely than not that we can take the hand down by bluffing, we will do it. This will give us a 50% chance or greater of winning this way, and we don't even have to worry about the money odds of the thing, or even what we have for that matter. So we watch to see what situations our opponents are folding more often than not, and we take advantage.