One of the most recognizable elements of ancient Egyptian culture is the distinctive writing style known as "hieroglyphics." Hieroglyphics are "pictographs," symbols/images that represent a certain word or phrase. Egyptian hieroglyphics are very ancient, dating back to the dawn of the dynastic period; however, they are not the oldest known form of writing, being predated by Sumerian cuneiform from Mesopotamia (Iraq). Like any language, over the centuries hieroglyphics changed, evolved, and branched off, essentially resulting in a different form of the Egyptian language for each period of Egyptian history.
The Old Kingdom had its own form of hieroglyphics, referred to as "Old Egyptian." This is the form of Egyptian that the Pyramid Texts and the inscriptions on the earliest mastaba tombs were written in. The language of the Middle Kingdom, called "Middle Egyptian" or "Classical Egyptian," is the language of much of ancient Egyptian literature, such as The Tale of the Shipwrecked Sailor and The Story of Sinhue. Hieroglyphics continued to evolve throughout the New Kingdom and beyond, becoming Late Egyptian and ultimately being replaced in later centuries by Hellenistic and Islamic languages.
The traditional hieroglyphics forms of Old and Middle Egyptian were primarily used in official capacities, such as inscriptions on funerary goods/stelae and carving and decoration the walls of tombs, temples, and palaces. For other functions, like paperwork and records relating to the duties of priests, scribes, and other government officials, the ancient Egyptians adopted a form of simplified hieroglyphic script called "Hieratic." Essentially, Hieratic was the "cursive" form of classical hieroglyphics. Later on in Egyptian history, another even more abbreviated hieroglyphic script evolved from Hieratic, called "Demotic." Demotic was much less pictorial and much more stylized than both Hieratic and Old/Middle Egyptian. From the advent of Christianity in Egypt during the Ptolemaic and Roman periods came "Coptic," still used to this day as the official language of the Coptic Christian Church in Egypt and Ethiopia. The Coptic language consists of an alphabet of 32 characters, created from the combination of Greek letters and elements of Demotic. Coptic is the first alphabetical language in ancient Egyptian history, ultimately replacing the pictograph-based languages of Classical Egyptian, Hieratic, and Demotic. Of course, following the Macedonian and Roman conquests of Egypt, Greek and Latin became popular means of communication, especially in port cities on Egypt's Mediterranean coast, like Alexandria.