That is, “LOL” no longer “means” anything. Rather, it “does something” — conveying an attitude — just as the ending “-ed” doesn’t “mean” anything but conveys past tense. LOL is, of all things, grammar.

Of course, no texter thinks about that consciously. But then most of communication operates below the radar, where things tend not to mean what they would literally. Over time, the meaning of a word or an expression drifts. “Meat” used to mean any kind of food. “Silly” used to mean, believe it or not, blessed.

We can see LOL-type expressions happening in speech…

Civilization, then, is fine. People banging away on their smartphones are fluently using a code separate from the one they use in actual writing, but a code it is, to which linguists are currently devoting articles.