Is it necessary to do this?

Is it necessary to use a poker tracking program if I want to play well? If so, which is the best, most user friendly, one?

Also, is it necessary to bet in holdem based on pot odds? I often notice the pros saying that they determined whether to play the hand, or that they should have played the hand, by determing the odds based upon what they had and the odds of that hand winning, as compared with the total money in the pot. Is this just a style of play, or is it essential to playing properly? How do you learn how to do this because im not sure I understand the odds theyre calculating...

Are they calculating that if they have say a 20% chance of catching a straight in order to win a 6000 chip pot and are facing a raise of 1000 that they should play the hand becaues 20% of the pot is 1200? If I'm understanding this correctly, after 5 hands you would in theory profit 1000 chips (5 * 200)... Is this correct?

I'm not sure if it's necessary, and I don't have one. However, it helps you analyze patterns in your own play, and shows which hands you tend to get attached to. It probably is a great tool to help you enhance your play, but I mean Doyle Brunson didn't use one...

I don't think a tracking program is necessary but it might help improve your game.
I view pot odds as a useful tool that I stick to most of the time. Statistically, you would do well to mind them in the long run. I certainly modified my play based on the competition and my read on them. ...and oh yeah, once in a while you just get a feeling you should call or raise when pot odds say don't!

Tracking softwae to track how you play is a must in my opinion. Live tracking software that tells you odds is also very good to use but don;t rely on it or you will never be able to play without it. Go to a table game and you will be sunk. Knowing these things without a tracker is very important.

Not necesery but like others have said its a good way to spot leaks in your game.
I also belive its more important for ring players then say MTT players and alot more important if your multi tabling(more then say 3-4 tables)

dont get caught up in stats and odds and crap like that....if u play your game and play situations properly u will do well..it takes lots of experience....but if u start thinking too much u will do poorly...just like anything....instincts are your biggest asset...and it take experience to get better instincts.....good luck to you friend

I actually started playing with Poker Tracker, helped me learn odds and stuff in poker, definitely useful as a beginner

Not at all necessary. I use it but that's because I like playing 4 tables at once plus surf through forums while I do so; this doesn't give me much time to learn player tendencies. PokerTracker was my fix to this.

I remember, a few nights ago, I forgot to turn on PokerTracker and I felt completely lost.

Again, not necessary in my honest opinion.

Getting experience at the table is WAY more expensive than Poker Tracker or Holdem Manager.

Not getting "caught up in stats and odds and crap like that" is even more expensive still and always will be with or without tracking software.

Both PT and Holdem Manager offer free trials. I would recommend you try both and see if you think either will help your game before you buy.

The absolute answer to your question is no, you don't have to keep track of your stats about other players, but you should be ABSOLUTELY CLEAR about it, THEY ARE KEEPING TRACK OF YOU.

If I give you 2-1 odds on a gamble of say, 'if I throw this ball into the air, will it travel 30 yards?' But you know nothing else about the situation, will you take the bet? You don't know even if it is a golf ball and I'm throwing in on cement, or if its a bowling ball and I'm on the beach. Point is you want to make decisions based on as much info as you can get, and both your questions (trackers and odds) are information tools, and as we live in an information age, why would you purposely avoid info?