In old days there were old typed casinos and people used to go there and play online roulette. In traditional casino there was no concept of trying or playing for practice but in online casino you can also play for practice and so for as online roulette is concern there are more opportunities to play it just for practice purpose.
As you know practice makes the man perfect and if you are more perfect in playing your game that is online roulette then you must be having more knowledge and there are more chances of winning when you are a good player who has good practice of online roulette.
But as for as the part of luck and fortune is concerned, we have no control over it and it is un certain. In online roulette game luck play an important part. A person having good luck can win even if he doesn't have much practical knowledge or experience and a person may lose the game even after having good and practical knowledge about the game but the most attractive thing is that a person will win sometimes with less experience and practice and can become rich this is totally because of his luck but still we cannot ignore the importance of practice.