When playing real online poker you get to use a lot of poker tools and software that is not available to you in a real life game. This can be a great advantage, but remember, the other players can use these tools too. So in fact by not using them you might actually be at a disadvantage.
Thankfully, as the online game has grown in popularity, a lot of online poker rooms will now supply you with some basic poker tools that you can use for free.
For example, Carbon Poker has produced a poker odds calculator that you can use on their tables.
For players that have never played offline or online, tools such as that calculator can be a great aid in getting to know the odds of the game, and should help you avoid making those marginal bets that are not profitable though they appear to be.
If you are just starting out with poker online then a great room to try is 888 Poker. They have some great bonuses for new players and very low micro stakes tables for beginners.