The title of "Pharaoh" actually comes to us from the Greek language and its use in the Old Testament. It originates in the Egyptian Per-aa, meaning "Great House", a designation of the palace, which first came to be used as a label for the king around 1450 BC, though it only became common usage some centuries later. For most of the time, the usual word for the king of ancient Egypt was nesu, but a whole range of titles were applicable to any full statement of a king's names and titulary.
According to Egyptian legend, the first kings of Egypt were later some of Egypt's most famous gods. We really do not know whether some of these individuals actually existed in human form or what regions of Egypt they may have ruled over. Only at the end of the Predynastic period, prior to the unification of Egypt, can we recognize specific kings who most likely ruled over either northern or southern Egypt. According to many sources, the first real king of Egypt, therefore ruling over the unified land, was Menes, who would have ruled Egypt around 3100 BC, but we have little if any archaeological basis for this name. Most scholars today believe that he may have been a king named Narmer, or more likely still, Aha, two figures that are better attested in the archaeological record.
However, Menes might have also been a legendary composition of several rulers. After these first rulers of a unified Egypt, the Egyptian monarchy lasted in a recognizable form for over three thousand years, basically ending with Cleopatra, though even Roman emperors attempted to style themselves as Egyptian pharaohs. We know of 170 or more specific pharaohs during this period of time. Although many changes occurred during that time, almost all of the fundamentals remained the same.
Kings were not only males, and unlike in modern monarchies, the ruler of ancient Egypt, whether male or female, was always called a king. In fact, Egypt had some very noteworthy female rulers such as Hatshepsut and others.
In ancient (Pharaonic) Egypt, the pinnacle of Egyptian society, and indeed of religion, was the king. Below him were the layers of the educated bureaucracy which consisted of nobles, priests and civil servants, and under them were the great mass of common people, usually living very poor, agricultural based lives. Except during the earliest of themes, when the highest official was apparently a Chancellor, for most of Egyptian history, the man or men just under the king were Viziers, (tjaty), a position that was roughly similar to a modern Prime Minister.
In many if not most accounts, the king is viewed as an incarnation of Horus, a falcon god, and the posthumous son of Osiris, who himself was a divine king slain by his brother, Seth. Horus fought his uncle for the return of the throne, and part of the accession process of the king was the proper burial of his predecessor, as Horus carrying out the last rites of Osiris. In fact, there are a number of cases where such an act may have been the legal basis for a non-royal figure's ascent of the throne. However, more usual was the succession of the eldest son, whose status as heir was frequently, if not always, proclaimed during his father's lifetime. Furthermore, there were a number of instances where this was taken a step further by the heir's coronation as a co-regent prior to the father's death. This has actually led to much confusion among scholars, because in some cases, the young heir began to count his regnal years only after the death of his father, while in other instances, he started to do so from the moment of his coronation. The ancient Egyptians did not use era dating as we do today (BC or AD), but rather relied on regnal dating of the king's rule, and therefore potential difficulties for modern, if not ancient, historians can easily be imagined.
The king himself (or herself) was the figure upon whom the whole administrative structure of the state rested. These god-kings usually commanded tremendous resources. The Pharaoh was the head of the civil administration, the supreme warlord and the chief priest of every god in the kingdom. All offerings were made in his name and the entire priesthood acted in his stead. In fact, he was himself a divine being, considered the physical offspring of a god. The myth of the ruler's divine birth centered on the god assuming the form of (or becoming incarnate in) the king's father, who then impregnated his wife, who accordingly bore the divine ruler.
Of course, the king was also subject to some rather grave responsibilities. Through his dealings with the gods, he was tasked with keeping the order, or ma'at of the land, and therefore keeping out chaos, often in the form of the enemies of Egypt from foreign lands. But he was also responsible for making sufficient offerings and otherwise satisfying the gods so that they would bless Egypt with a bountiful Nile flood, and therefore a good enough harvest to feed his people. When he failed at these tasks, he could bear not only blame, but a weakening of the state and thus his power. In drastic cases, such as at the end of the Old Kingdom, this could actually lead to a complete collapse of the Egyptian state.
Even today, many questions remain about the kings of ancient Egypt. We have a fairly good idea of their order through time, though often scholars disagree about specific dates related to our current form of the calendar. Our evidence of their order comes mostly from various "kings' lists, that almost exclusively were made during the New Kingdom. Another source is the Egyptian history written by Manetho, an Egyptian priest, but over the years, there have been modifications to both the kings' lists and Manetho's history made through archaeological discovery. Nevertheless, there are periods of Egyptian history, particularly those known as intermediate periods, where very little information exits on who ruled (usually only a part of) Egypt.
Basically, Manetho divided up ancient Egyptian history into thirty dynasties, though this division is a bit difficult, and modern scholarship has proven it to be not completely (and sometimes not at all) accurate. Most of the time, a dynasty consisted of a related family of rulers, though sometimes dynasties seem to have been broken up due to the establishment of a new capital. In a number of instances, modern Egyptologists believe that he may have been incorrect about the end of a family line.
Even today, the power that an ancient Egyptian pharaoh commanded in ancient Egypt and the resources under his control can seem staggering. One need only think in terms of the Great Pyramids, the wealth of gold and the grand temples to gain some understanding of their power. They commanded resources that many modern day states would be hard pressed to emulate, and they did so at a time when much of the remainder of the ancient world were struggling for a foothold in history.
Magawish Tours
Cairo Short Break at Mena House Oberoi Hotel

Experience the unique Short Break Tour in Cairo where  you will discover the Giza Pyramids, the Great Sphinx and the Valley Temple of Chefren. Then to the Egyptian  Museum, enjoying the golden treasures of the king Tut among many other artifacts during your tours.