Snowflower Chess is the best environment to practice chess. By playing with a computer, chess skills will improve widely from beginner to grand master level.
Chess is a board game that takes place between two players. You can play easily, but it is very difficult to master. You can play with computer with 20 levels of difficulty from beginner to advanced level. Choosing the best strength for you will improve your chess skills. You can play with a computer of greater strength than the human grandmaster if you want.
Note: Now requires OS X 10.10 or later