ENA6 question 1a - technology and language change

Here's the new Haribo prize question, based on a 1a ENA6 question focused on technology and language change.

Comment linguistically on three processes used to create or write the following examples of computer-mediated communication:

FYI (For your information)
Dat (That)
i dont no what yr doin (I don’t know what you’re doing)
cya (See you - signing off at end of online chat)
L8er (Later - signing off at end of email message)

Remember, you just need to accurately identify and label 3 processes going on with these words or how they've been written/typed. The best 2 answers get that lovely Haribo.