Type the phrase "In 2019, I'll ..." and let your smart­phone's keyboard predict the rest. Depending on what else you've typed recently, you might end up with a result like one of these:

In 2019, I'll let it be a surprise to be honest.

In 2019, i'll be alone.

In 2019, I'll be in the memes of the moment.

In 2019, I’ll have to go to get the dog.

In 2019 I will rule over the seven kingdoms or my name is not Aegon Targareon [sic].

Many variants on the predictive text meme—which works for both Android and iOS—can be found on social media. Not interested in predicting your 2019? Try writing your villain origin story by following your phone's suggestions after typing "Foolish heroes! My true plan is …" Test the strength of your personal brand with "You should follow me on Twitter because …" Or launch your political career with "I am running for president with my running mate, @[3rd Twitter Suggestion], because we …"

Gretchen McCulloch is WIRED's resident linguist. She's the cocreator of Lingthusiasm, a podcast that's enthusiastic about linguistics, and her book Because Internet: Understanding the New Rules of Language is coming out in July 2019 from Penguin.

In eight years, we've gone from Damn You Autocorrect to treating the strip of three predicted words as a sort of wacky but charming oracle. But when we try to practice divination by algorithm, we're doing something more than killing a few minutes—we're exploring the limits of what our devices can and cannot do.

Your phone's keyboard comes with a basic list of words and sequences of words. That's what powers the basic language features: autocorrect, where a sequence like "rhe" changes to "the" after you type it, and the suggestion strip just above the letters, which contains both completions (if you type "keyb" it might suggest "keyboard") and next-word predictions (if you type "predictive" it might suggest "text," "value," and "analytics"). It's this predictions feature that we use to generate amusing and slightly nonsensical strings of text—a function that goes beyond its intended purpose of supplying us with a word or two before we go back to tapping them out letter by letter.

The basic reason we get different results is that, as you use your phone, words or sequences of words that you type get added to your personal word list. "For most users, the on-device dictionary ends up containing local place-names, songs they like, and so on," says Daan van Esch, a technical program manager of Gboard, Google's keyboard for Android. Or, in the case of the "Aegon Targareon" example, slightly misspelled Game of Thrones characters.

Another factor that helps us get unique results is a slight bias toward predicting less frequent words. "Suggesting a very common word like 'and' might be less helpful because it's short and easy to type," van Esch says. "So maybe showing a longer word is actually more useful, even if it's less frequent." Of course, a longer word is probably going to be more interesting as meme fodder.

Finally, phones seem to choose different paths from the very beginning. Why are some people getting "I'll be" while others get "I'll have" or "I'll let"? That part is probably not very exciting: The default Android keyboard presumably has slightly different predictions than the default iPhone keyboard, and third-party apps would also have slightly different predictions.

Whatever their provenance, the random juxtaposition of predictive text memes has become fodder for a growing genre of AI humor. Botnik Studios writes goofy songs using souped-up predictive keyboards and a lot of human tweaking. The blog AI Weirdness trains neural nets to do all sorts of ridiculous tasks, such as deciding whether a string of words is more likely to be a name from My Little Pony or a metal band. Darth Vader? 19 percent metal, 81 percent pony. Leia Organa? 96 percent metal, 4 percent pony. (I'm suddenly interpreting Star Wars in quite a new light.)

The combination of the customization and the randomness of the predictive text meme is compelling the way a BuzzFeed quiz or a horoscope is compelling—it gives you a tiny amount of insight into yourself to share, but not so much that you're baring your soul. It's also hard to get a truly terrible answer. In both cases, that's by design.