Ig is the short form for instagram. It is much like facebook's short form Fb.
Clarence-Hey how are you?
Janet-Well my selfie on ig got tons of likes. I feel #famous
98👍 61👎
Used as opposed to HAHA, haha, hahaha, lol or hehe. Ha means something was moderately funny but not funny enough that you're laughing hard-more that you got a kick out of the joke. Used also when you don't want to seem like you're fanning over someone and seem too excited.
Thomas: My mom told me to get a life. I'm like, Mom! I have a life I'm breathing.
Leesha: Ha