"OMG! LOL's in the OED. LMAO!"

If you find the above string of letters utterly unintelligible, you are clearly an internet "noob". The internet slang term "LOL" (laughing out loud) has been added to the Oxford English Dictionary, to the mild dismay of language purists. The OED defines LOL as an interjection "used chiefly in electronic communications... to draw attention to a joke or humorous statement, or to express amusement". The phrase was ushered in alongside OMG (Oh My God), with dictionary guardians pointing to their growing occurrence "in e-mails, texts, social networking... and even in spoken use".
• :D (smileys) - Simple and clear but may appear childish. Are you a Comic Sans fan?
• ROFL, LMAO, BWL (Rolling On the Floor, Laughing / Laughing My Ass Off / Bursting With Laughter) - Even more annoying than LOL.
• !!! - One is fine, three reeks of desperation: 'Look!!! I made a joke!!!' Yes, we noticed.
• Haha, Hehehe, Arf arf - The safe option. Effective but not very imaginative. Were you really laughing?
• Hilarious! How funny! - You are living in the dark ages.
Source: Migalhas