Symbol is typically used online for 3 things;
1. In online chat or role play the asterisks are suggesting someone is making an action at you or they feel like doing something to someone strongly.
3. Making a correction to a previous mistake.
In order of the definitions of asterisk:
1. *tackles* you to the ground! or simply type (*tackles*) cause you just can’t contain your emotions and have no other way to express yourself.
2. *grins* If you get what I mean?
3. helo!… I mean *hello! (or hello!*) – showing correcting typo