Tone tags are a method of communicating tone and emotion through texting, posting, or any other form of online communication. A list of the most commonly used tone tags follows.
/srs - seriously
/gen - genuinely (can also be /g)
/j - jokingly
/hj - half-jokingly
/nf - not forced
/lh - light-hearted
/nm - not mean
/s - sarcasm (can also be /sar or /sarc)
/p - platonically
/genq - genuine question
/pos - positive tone
/neg - negative tone
/neu - neutral tone
/nfa - not looking for an answer
/lfa - looking for an answer
A full list of tone tags can be found here.
Tone tags are never meant to be used as a joke. It ruins the point of them and can be very confusing.