Solving Sudoku puzzles

My trip to Niagara was great. Niagara was just gorgeous.
During our trip, one of our friends had this book of sudoku puzzles. This was the first time, I tried solving a sudoku. I tried hard but failed :(
I became curious on how sudoku's can be computaionally solved. I thought Heuristics might be a better approach. After coming back I googled for it and was taken to Wikipedia. The wiki on sudoku was gud and gave me an impression that Sudokuz can be solved using Backtracking and Don Knutz Dancing Links Algorithm. This is the first time, I am hearing about something called constraint programming.