Clueless

It's no secret that I'm typically behind the times in trendy technological developments.  I just got my first iPod last Christmas; I didn't join facebook for an internet eternity, and then waiting a year to actually use it; I didn't even know what a blog was when all of my friends started reading and writing them; I finally gave up using floppy disks in 2006; and I didn't have a cell phone in high school and didn't start texting till, well, that's embarrassing to say. 

Even though I'm generally behind the times, I eventually figure things out and catch up.  But I have to admit that there's one trend I just can't figure out.  What the heck do @ and # mean?!?  So I get that you put @ before a person's name in facebook or a blog comment to signal you're responding to that particular person.  However, I don't see why this is at all necessary.  So I don't do it.  Call me old fashioned.  But the lack of # in my facebook statuses is not a statement (although I don't ever see myself using it), it's a complete lack of understanding.  I don't get it.  I can't figure it out.  I need someone to explain it to me.  Help!  I must be getting old.