While one might think the pencil, invented by Hymen Lipman, has been seeing less frequent use since the invention of the pen decades ago, it seems Sudoku proved otherwise. Though the pencil was invented a mere 150 years ago (when it was protested by many school teachers because it “encouraged careless thinking”), it’s been the quintessential writing tool for any classroom.
Sudoku, as you likely know, is a logic based number puzzle. The objective of Sudoku is to fill a 9 by 9 grid with the numbers 1 through 9 so that all 9 columns, rows, and 3 by 3 squares have the numbers 1 through 9. Though the puzzle was popular internationally in 2005, it had first become popular in Japan some 20 years earlier.
Back in 2008, The Independent of London reported a 700 percent increase in pencil sales for the year of 2006, during the height of the Sudoku craze. If you’re in the mood to try out one of the 5,472,730,538 Sudoku puzzles, you can visit this website here: http://www.websudoku.com/