Allows you to select levels by their difficulty rating. When you finish a level , press Skip or Select a new game, the program will skip levels with difficulties that are not selected. This has no effect on loading a level directly.

You can check as many as you want. They are:

Kids Very easy levels that kids should enjoy playing
EasyEasy levels but you might have to think a little
MediumThese levels are good levels that will take some thought
HardThese levels will take a lot of thinking
DeadlyWhat do you think, some of these are over 2000 moves