An abbreviation for "Laugh Out Loud" that is used in cyberspace. It is rarely (if ever) meant literally.
Maybe there was a time that it LITERALLY meant "Laugh Out Loud", however, I have been active in cyberspace for over ten years and am unaware of this time.
What “lol” is, is simply one of the many ‘online lingoes’ that are used to communicate things that
IRL (in real life) would otherwise be communicated through either voice tone or body language. In particular, “lol” is used to signify that the individual typing it finds
something humorous about what they are saying EVEN IF this individual typing it
may not literally be "laughing out loud”
"lol" and most other 'online lingo' also tend to be used in text messages and
high school note-passing. And with the exception of text messages (when laziness may ensue), the first letter to “lol” is not usually capitalized,
even when it is the start of a sentence or a sentence by itself.