who are you???

So this guy started at my work this week and he works in a diff. department so I don’t see them and today he said, “hi beth!” and I was like “hi!” (why are you talking to me? I don’t know you) the way he said hi was an, ‘I know you’ hi. And I don’t know who this guy is. It is kind of frustrating. Maybe I am reading in to it and he doesn’t know me and is just a being nice, or a freak. We will see. All I know is that I googled him and I still don’t know how I know him….weird.