'LOL' is one of several texting expressions that convey nuance in a system where you don't have the voice and face to do it the way you normally would.

People have been warning us that language was going to the dogs ever since Latin started turning into French. Yet the dogs in question never seem to emerge yelping on the horizon.

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.

John McWhorter Quotes