The Sun God, often considered the most important god, was the Ra. He was thought to be a baby in the morning, when the sun rose, a tall young man at noon, and an old, frail man at night. Every day, he was born again, and every day, he died.
Nut, the sky goddess, was the sky itself, and was married to Geb, the earth god. They were so...uh...busy...that the god of air was told to hold them apart by Ra.
Osiris was the king of the dead. He had, in brief, been killed by his brother in a cruel trick, and his wife, Isis had mourned for him. She'd brought him back to life, but his evil brother, Set, had again killed him and scattered the pieces of his body to the corners of the earth. Isis found them, and pieced him back together. They produced Horus, their heir, and then Osiris died again, to become god of the underworld. Horus went on to take over the reign from Set.
And these are only the basic gods of the Egyptians. They had many, may more, minor gods, like Sahkmet, Sheb, and others. Sometimes I wonder, how did they keep track of who they needed to pray to. They spent most of their life preparing for death, because they thought that in death, Osiris would accept them into his world. Spent most of their life preparing for it's end. Confuses me, but it worked for the Ancient Egyptians.