"ROFL" is a common acronym for laughter: "Rolling on Floor, Laughing". It demonstrates levity and a sense of humor in your online messaging. There are common variations of ROFL, including LOL (Laughing Out Loud), LMAO (Laughing My Ass Off), and ROFLMAO (Rolling on Floor, Laugh My Ass Off). In the United Kingdom, the expression PMSL is also common.
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