A Pharaoh is a ruler in ancient Egypt. It is a title used in many modern discussions of the ancient Egyptian rulers of all periods; the title originates in the term pr-aa which means "great house" and describes the royal palace. The title of pharaoh started being used for the king during the New Kingdom.  For simplification, however, there is a general acceptance amongst modern writers to use the term to relate to all periods.
List of Pharaohs
A list of pharaohs can be found at this category page: Pharaohs.
History of the Pharaoh title
During the Old Kingdom, the king of Egypt (not called the Pharaoh until the New Kingdom) became a living god, who ruled absolutely and could demand the services and wealth of his subjects. Pharaoh, meaning "Great House", originally referred to the king's palace, but by the reign of Thutmose III (ca. 1479-1425 BC) in the New Kingdom had become a form of address for the person of the king. 
During the battle with Apophis, Carter Kane, hosting Horus at the time and also acting as the Pharaoh of the Gods, is offered the position of Pharaoh. With the support of his family and friends, Carter accepts the position and as his first act, leads the magicians and gods into battle with Apophis. After Apophis is destroyed, Carter is officially crowned as the first Pharaoh in over a thousand years, but leaves the day to day running of the House of Life to its Chief Lector Amos Kane while he runs Brooklyn House and grows up as he is only fifteen.
Crowns and headdresses
The red crown of Lower Egypt - the Deshretcrown - dates back to pre-dynastic times. A red crown has been found on a pottery shard from Naqada, and later king Narmer is shown wearing the red crown on both the Narmer macehead and the Narmer palette.
The white crown of Upper Egypt - the Hedjet crown - is shown on the Qustul incense burner which dates to the pre-dynastic period. Later King Scorpion was depicted wearing the white crown, as was Narmer.
The combination of red and white crown into the double crown - or Pschent crown - is first documented in the middle of the First dynasty of Egypt. The earliest depiction may date to the reign of Djet, and is otherwise surely attested during the reign of Den.
Egyptologist Bob Brier has noted that despite its widespread depiction in royal portraits, no ancient Egyptian crown ever has been discovered. Tutankhamen's tomb, discovered largely intact, did contain such regalia as his crook and flail. No crown was found however among the funerary equipment.
It is presumed that crowns would have been believed to have magical properties. Brier's speculation is that crowns were religious or state items a dead pharaoh could not retain as a personal possession. The crowns may have had to be passed along to a successor.