What are Sudoku Puzzles?

Sudoku was invented in 1979 by a 74–year old retired architect named Howard Garnes, who was also a freelance puzzle maker. It was a puzzle that had a grid that was partially filled with numbers. The solver had to fill in the rest of the squares with the right combination of numbers. The game first appeared on the New York publication Dell Pencil Puzzles and Word Games under the name Number Place.