Most people don't know what it means, but I do. It is owo, but cuter. It's when someone pretends to understand what it is, or is someone is being cutesy. Sort of like a simpler version of 'wtf does that mean' or 'hehehehehehehehehe........ no one will know this...'
Friend: Did you eat my cookies?
Me: No
Me: *w*
Friend: Run. I know what that means. r u n
Me: Oh sHiT-