Texas Hold’em Poker has become the fastest growing game on the Internet. Play it a few times and you will understand why. It’s addictive. Fast. Entertaining. Colorful. And there you are, playing live with people all over the globe, a great virtual casino experience – and real money is being won by people just like you and me. Like the people who play slots or video poker terminals, most people just play poker online for fun. Don’t get me wrong. They will love to win; they just aren’t prepared to do the homework necessary to get really good at the game and win consistently. Who has time for that ?
Online poker adds several interesting wrinkles to the game of Texas Hold’em. So much is changed in fact, that there are a whole new set of game strategies. The odds of winning the online version of this game are now stacked even more in the favor of the better educated players. This is one of the secrets to real success at the virtual table.
Online, you can watch a real game as long as you want, for no cost and no risk. Watching a table can teach you a lot about the players and their betting style and the game in general. Watching players for “free” is one of the great advantages of online poker.
Tacking notes is another great strategy in Online Poker. There is nothing wrong or unethical about keeping notes on other players. Some Online Poker rooms even provide a feature that allows you to take notes while you play. This feature facilitates the building of a database around the playing styles of consistent players. Our advice is to record what kinds of hands they play, how quickly they react, and to record detail on betting and raising behaviour.

Source : Playing Texas Hold’em Online – The Professional’s Guide, A.J. Mills (2004)