Need help on the mysteries of the Great Pyramids!!?

I am doing a speech on the coincidences of the pyramids and the secrets behind it, i have found A LOT of information about it but there are two things i can't quit understand.. If someone can please help me understand this two facts that will be great..... I keep reading about the Great Pyramids in Egypt and something about the Nile Delta?? Ok what exactly does the Nile Delta have to do with the Great Pyramids? And the second one is, the Great Pyramids are aligned with the North Pole? Those two strange facts get me confused while i read it, they use words i dont understand to describe it... Can anyone help me understand these two facts? Put it in easier words for me?