|ASL||Age, sex, location|
|ASLP||Age, sex, location, picture|
|morf||Male or female|
|WRU||Where are you|
|LMIRL||Let's meet in real life|
|MIRL||Meet in real life|
|Slide into your DMs||To send a direct message on Twitter|
|DOM||Dirty old man|
|Facestalking||Looking through someone's pictures on Facebook|
People send "A/S/L" when they want to know the recipient's age, sex, and location (where they live or where they currently are). You will most likely see it in online chatrooms or texts when communicating with a stranger or an acquaintance.
Origin of A/S/L
The acronym A/S/L originated in the late-1990s. It is unclear who created the acronym, but it grew in popularity as strangers began connecting in online chatrooms. Because users could not see each other (video chat and image sharing were uncommon in those days), they'd often ask for fellow users' A/S/Ls, to better understand with whom they were connecting.
People send A/S/L as a standalone question ("A/S/L?"), or in a complete sentence ("Can you send me your A/S/L?"). Since there are a lot of pervs out there, people should be cautious when replying to an A/S/L request.