A notation used to signal the use of sarcasm in a text, instant, or various mobile device message. Often used to eliminate confusion and arguments caused by texting misinterpretations.
The generally accepted practice includes adding an "s" directly following or close to the ending punctuation of the message.
"This rush hour traffic is the best.s"
"I would have done her too if I was in your situation. S"
"Sweet sweater vest there chief! s"
".s", ". S", and " s" all denote texting sarcasm.