Why would a guy I don't know say hi to me in the halls?

Today some guy I've maybe seen around and never talked to (he's not in my grade or I'd know) say hi to me in the school hallways?

This is exactly what happened:

I was walking down an empty hallway (except for him) and he says "Hi"

I smile because that's what I do when I'm confused or something is awkward and I keep walking down the hall.

His face goes red and he smiles back then looks at the ground and walks past.

I don't know him and I think I might have seen him somewhere but I'm not sure. Why randomly say Hi?

I don't have a clue who he is?

Did he confuse me for someone else?

... so, WTF was that? :/
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+1 y
Wow, thanks guys.

I've never in my life been subjected to random hellos from people I don't know. So geez sue *me*. -.-

I am anti-social. I think it's incredible weird to say hello to people you don't know. It flat out stunned me that people would do that. I wasn't looking for people to tell me he liked me (or whatever else), I'm not that conceited (in fact the opposite).

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+1 y
I was simply stating what happened and why someone would do this. The gender was irrelevant.

I didn't need all the hatred..
Why would a guy I don't know say hi to me in the halls?
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