"LOL" and "LOLZ" are often spelled all uppercase, but can also be spelled "lol" or "lolz". Both versions mean the same thing. Just be careful not to type entire sentences in uppercase, as that is considered rude shouting.
Example of LOL usage:
- (first user:) Bwahahaha! The pizza man just came to my door, and he was wearing pink pants and cowboy boots!
- (second user:) LOL! That is some kind of fashion sense! ROFL!
The LOL expression, like many cultural curiousities of the Internet, is a part of modern English communication.
Read more Internet abbreviations and shorthand expressions...