"Sudoku is a logic-based number placement puzzle. The objective is to fill a 9×9 grid so that each column, each row, and each of the nine 3×3 boxes contains the digits from 1 to 9, only one time each.
The puzzle setter provides a partially completed grid."
There are 4 levels of difficulty - Gentle, Moderate, Hard and Diabolical.
As u can see, i solved a 'Diabolical' for the 1st time & must have taken some 40 -45 minutes(Sudoku experts will scoff at my timings :-p) to solve it.
p.s - solved it sometime back but my scanner was on the blink. Had carefully preserved the portion of paper until now :-p.