At Scanraid.com Andrew has a very interesting collection of methods to solve Sudoku. I discovered some new methods in solving Sudoku’s.
All techniques are divided in three kind of methods. Basic Strategies contains the methods like Naked Pairs, Naked Triples, Naked Quads, Hidden Pairs, Hidden Triples, Hidden Quads and Intersection Removal.
The next page contains the Fishy Strategies consisting of methods like X-Wing, Sword-Fish, Jelly-Fish, Multivalue-X-Wing, Turbo-Fish, Finned X-Wing, Sashimi Finned X-Wing.
And the last page contains the Advanced Strategies like Singles Chains a.k.a Simple Colouring, Multi-Colouring, Y-Wing (also known as XY-Wing), Y-Wing Chain, XY-Chains, XYZ-Wing, WXYZ-Wing, Aligned Pair Exclusion, Remote Pairs, Unique Rectangles and Guardian/Broken Wings.
With these stratgies you must be able to solve all Sudoku’s. Happy Puzzling!