Twitter has been filled in the past weeks with grids of green and yellow squares, all tagged with the same relatively-inconspicuous name. These are from users sharing results from a viral word game, dubbed Wordle by its developer, Josh Wardle. Upon opening up the game's website, players are presented with a five-by-six grid of squares. They can fill each row with any five-letter word, with the goal of guessing the word of the day.

This would be rather impossible, as the English language has over a hundred thousand different five-letter words, but players are given feedback after each guess. Letters that aren't in the word turn grey, and letters that are in the word but in the incorrect space turn yellow. Correct letters in the correct space turn green. This means players have six guesses overall to pare down the entire possible range of possibilities to a single correct result.

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A Wordle grid with correct guesses displaying a specific pattern.

While the game seems rather simple, there's a couple of different factors that make it so engaging. Players can just guess randomly, but that would only be efficient if the word of the day was also random. Instead, it's guaranteed to be a word from the English language, which means there are specific quirks and oddities to be exploited. Just as any keen Scrabble player knows, certain letters appear more or less often in most words. Vowels are a primary example, as they're used universally while making up not even a fifth of the alphabet. So starting words with lots of vowels are a good bet, along with some of the more common consonants. "RATIO" is a good bet, covering three vowels and two common consonants. Another fun pick is the less-common "SOARE", an obscure term for a young hawk that gives the most common vowel (E) along with two other vowels and common consonants.

This degree of strategy can also serve to set different kinds of players apart. Some might prefer to use the same starting word every day, giving themselves a consistent base to work from. Others might cycle between a range of trusted standards to offer a small amount of variety. And those going even further will use a different starting word every day. This is a less perfect way to play since the list of "optimal" starter words is fairly small, but Wordle isn't that hard a game. Players will get the hang of it fairly quickly, and once they do it's easy to work in a variety of personal flourishes.

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But even beyond the game's mechanics itself, it's helped by its shareability. Wardle implemented the emoji grid feature after it was proposed by Twitter user @irihapeta. This means players can post their results online without spoiling what the answer is. An asterisk (*) on a result denotes that a player is playing on "hard mode," which means they have to use any discovered letters in future guesses. This prevents them from ruling out five letters at a time, but is mostly just a different style of play, as opposed to being strictly harder.

Wordle grids also offer up a second, more meta-level of gameplay, especially when combined with starting words. If someone uses the same starting word each day, it's easy to reverse-engineer it from their grids. Knowing what they started with can then give players a leg-up on future days, all by just looking at what other people's results were. This is technically cheating and only works if others are consistent with both their starting words and sharing their results. But it's just another example of how complex the seemingly-simple game can be. At the end of the day, Wordle is good, clean fun, perfect for bringing together friends and family in new ways.

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