CT-Art is a chess tactics trainer. There is to my knowledge no other program of similar standard available that gives this level of quality training to a chess player.
Finally a new and improved version of the legendary CT-ART has been released! This excellent tactics course has been voted more than once by the chess experts as the best chess training program. CT-ART is an indispensable training tool for intermediate players. The new version sports a convenient user interface and adds 1,000 training exercises, bringing the total to 2,200 basic exercises and 1,800 auxiliary exercises altogether.