If you’ve ever opened a newspaper or puzzle book, chances are you’ve seen a Sudoku grid: nine rows, nine columns, and nine boxes, each waiting to be filled with numbers one to nine. At first glance, it looks like a maths test. But Sudoku is not about calculation at all. It is about logic, patience, and the satisfaction of watching a blank grid slowly transform into a completed pattern. Today Sudoku is one of the most popular puzzles in the world, but its journey from origin to global craze is as fascinating as the game itself.Although Sudoku feels modern, its roots go back centuries. The idea of arranging numbers in grids has been around since ancient times. Mathematicians in China created magic squares thousands of years ago, in which numbers were arranged so that the sums of rows, columns, and diagonals were always the same. In the 18th century, Swiss mathematician Leonhard Euler developed something called “Latin squares”, arrangements of symbols where each appeared only once in a row or column. Euler could never have guessed it, but these ideas would later inspire the game we now know as Sudoku.The puzzle took its present form much more recently. In 1979, an American puzzle inventor named Howard Garns created a game called “Number Place” for a puzzle magazine. The rules were simple: fill the grid so that every row, column, and smaller box contained each number once. Readers enjoyed it, but it remained a niche pastime. The breakthrough came in the 1980s, when the puzzle was published in Japan. The Japanese puzzle company Nikoli gave it the name “Sudoku”, short for a phrase meaning “single number”. With its clean rules and logical challenge, Sudoku quickly became a hit in Japan.For nearly two decades, Sudoku was mainly popular in Japan. That changed in the early 2000s when a British judge named Wayne Gould discovered the puzzle on a trip to Tokyo. Intrigued, he spent years writing a computer program to generate Sudoku puzzles of different difficulties. He convinced newspapers in Britain to publish them, and within months, Sudoku spread across Europe. Soon it appeared in newspapers and magazines worldwide, often next to the crossword. By 2005, Sudoku fever had swept through classrooms, offices, and households. What had once been a quiet puzzle was suddenly a global obsession.Part of Sudoku’s appeal lies in its simplicity. The rules can be explained in a single sentence: fill the grid so each number appears once in every row, column, and box. Yet behind that simplicity hides endless variety. Some puzzles can be solved in minutes, while others stump even experienced players for hours. This balance of clarity and challenge has made Sudoku popular with people of all ages, from children learning logic to grandparents keeping their minds sharp. Unlike crosswords, Sudoku does not depend on language or trivia knowledge. A child in India, a teenager in Brazil, and an adult in France can all solve the same puzzle, because numbers are a universal language.Sudoku has also evolved beyond its classic 9×9 form. Newspapers sometimes feature 4×4 grids for beginners or giant 16×16 versions for experts. There are variations like “Killer Sudoku”, which adds small sums in outlined boxes, or “Samurai Sudoku”, where multiple grids overlap. Puzzle designers enjoy inventing twists, but the heart of the game remains the same: using logic to eliminate possibilities until only one solution fits. With the rise of computers and smartphones, Sudoku has become even more accessible. Apps allow players to choose difficulty levels, get hints, or even race against the clock. What began as a paper-and-pencil pastime now lives in millions of pockets around the world.Scientists have also studied Sudoku. Mathematicians analyse how many clues are needed to make a valid puzzle (the answer is at least 17). Psychologists study how solving Sudoku can improve concentration and problem-solving skills. Teachers use it in classrooms to introduce logical thinking. Even neuroscientists recommend it as a way to exercise the brain, because it requires memory, focus, and pattern recognition. Far from being just a pastime, Sudoku has become a tool for learning and mental health.Yet perhaps the most important reason Sudoku endures is the feeling it gives. At the start, the grid seems impossible, filled with blanks and possibilities. But with patience, each number begins to find its place. A nine here rules out another nine there, and slowly the puzzle opens up. Completing a Sudoku brings a unique satisfaction: proof that persistence and clear thinking can turn confusion into order. It is the same satisfaction that has driven humans to solve riddles, crack codes, and complete puzzles throughout history.Sudoku is not JapaneseAlthough the name is Japanese, the puzzle was first created by American Howard Garns in 1979.The name means single numberSudoku is short for “Sūji wa dokushin ni kagiru,” which translates to “the numbers must be single.”The shortest puzzle has 17 cluesMathematicians proved that any valid Sudoku needs at least 17 starting numbers to have a unique solution.Sudoku nearly stayed hiddenIt was little known outside Japan until British judge Wayne Gould introduced it to newspapers in 2004.World championships existThe first World Sudoku Championship was held in Italy in 2006, and it continues every year.Computers helped the crazeGould’s computer program could generate endless new Sudoku puzzles, making daily newspaper publication possible.Sudoku isn’t mathsDespite using numbers, Sudoku doesn’t involve adding or multiplying—only logic and reasoning.Samurai Sudoku multiplies the challengeThis variation overlaps five grids, creating one giant puzzle for experts.
