Lol

Short for "laugh out loud". It is supposed to be used for the purpose of showing others that you liked what they said to the point that it makes you laugh intensely but as usual it has been mistakenly used on the internet (and mostly by teenagers) who just apply it to almost every one of their sentences. At the moment it's meaning has been altered due to what is mentioned above and it should be considered as a mixed expression of 1.liking, 2.surprise, 3.question, 4.undefined emotion and 5. when you face something unbelievable. It is definitely not as strong as laughing out loud, it is a common abbreviation, a tad closer to funny but it can be used pretty much everywhere (ok don't use it if you are reffering to something sad, that is going to be uncool).