About position
Position is one of the most important factors in poker. Being in position means that you get to act after your opponent. Being out of position means the opposite and you act before your opponent. The reason being in position is so valuable is because you get more information before you make your decision. I'll give you a little example of how it would work. Let's say you are on the button with j10 of hearts and your opponent is under the gun with pocket 9s at a 1/2 no cash game. He opens the action to 8$ it folds to you. You can 3 bet him to 24$ (not saying that's the best play in this situation but it's a play that I would definitely mix in every now and then just to keep my opponent guessing) now the blinds fold and he calls. Now your opponent has to play 3 streets of betting with you getting to see how he reacts to every card that comes. So the flop comes Ah,2d,6s though you opponent is ahead right now and you only have 6 outs to improve and beat him which is roughly 24%. But because it is likely that you have an ace in your range being that you three bet preflop he elects to check and you fire off a cbet of 35$ into a pot of 51$. Now your opponent is in a tough spot he has to decide if you have an ace or not. But your opponent decides to play tough and call once. But he has already shown weakness now a k comes on the turn giving you a couple more outs but also another over card out there, your opponent checks again the pot now has 121$ in it and you fire a second barrel of 65$ and only a wild man is going to call on that board with pocket 9s (unless your table image is terrible). So you just took down a 121$ pot with Jack high. Anyways I hope that this scenario helps you understand position and it's importance.