Before you are willing to choose side, either the white or the black, you have to pick up your desired difficulty level. When the computer plays at its normal level, it will think for around 5 seconds and it can be challenging for normal players. Casual flash chess thinks for about one second. This is a good setting for quick matches during a coffee break. Novice flash chess plays at its lowest level. Use this setting if you are still learning chess or if you want to beat it quickly.