First Wordle was a grassroots hit that went viral, then the the online word puzzle was bought by the New York Times for a seven-figure sum, and now it has spawned legions of imitators.
From Nerdle to Worldle, the simple format has been copied in dozens of new ways in recent weeks, sometimes to satisfy urges unfulfilled by the original, such as the opportunity to play more than once a day, but also to step up the challenge, profit from online advertising, or tap into niche interests.
