The invention of a written language is a defining moment for a civilization. At that point, the people can record their history, write their stories, tabulate administrative measures, and preserve for generations to come the revelations in science and philosophy. Archaeologists have learned much about past societies and languages from what written records they unearth.
Sumer (4500 B.C. – 1900 B.C.), the earliest civilization to settle in Mesopotamia, earns the award for earliest written language. The Sumerians wrote on clay tablets using cuneiform script, characterized by the wedge-shaped marks made by a reed stylus. Its development started around 3200 B.C. with pictographs and, later, phonograms to express ideas.  (Pictographs use pictures of the concept to present it, while phonograms use symbols that represent a syllabic sound.) Cuneiform eventually evolved to a complex enough degree for the writing of such works as the Epic of Gilgamesh, an epic poem twelve tablets long.
Most if not all of the Mesopotamian civilizations that succeeded Sumer used cuneiform. Meanwhile, in the Egyptian kingdom starting at about the same time as the invention cuneiform, papyrus outclassed clay tablets as the writing surface of choice. The English word paper comes from the use of papyrus in ancient Egypt for writing. By soaking papyrus leaves to the point of rotting then pounding them flat in a basket-weave pattern on top of one another, the Egyptians created a form of paper. 
Rather than cuneiform, the Egyptians used hieroglyphics, a logographic and pictographic form of writing. (Logographic means that each character represented a word or sound.) Until the discovery of the Rosetta Stone in the late 18th century and its deciphering in the early 19th century, archaeologists, historians, and linguists did not know how to read Egyptian hieroglyphics.
Papyrus flourished in the subtropical climate of Egypt but, further north, peoples had to turn to other materials. Among pastoral nomads and other communities that herded livestock, vellum, prepared animal skin, served as paper.
In ancient China, bamboo, silk, and animal bones both took their turns as the paper material of scribes. So far as historical records reveal, in A.D. 105, the eunuch Cai Lun (蔡伦) of the Han Dynasty (206 B.C. – A.D. 220) invented paper by soaking, blending, and pressing different fibers, including hemp, tree bark, and fishnets.  Similar to ancient Egypt, the Chinese developed a logographic, pictographic writing system, called zhōngwén (中文). (For more on the Chinese written language, developed independent of Mesopotamia, see this post.)
While eastern civilizations played with pictographic languages, the Phoenicians (1500 B.C. – 300 B.C.) to the west graduated from a cuneiform script in the first centuries of their existence to an alphabetic script at around 1000 B.C.  The Phoenician alphabet had 22 characters that were written horizontally from right to left, like the Arabic alphabet still used today. Trading with other nations of the Mediterranean, Europe, and North Africa diffused this form of writing to the Greeks, Latins, and others.
The Romans developed the Latin alphabet, used in English today, from the written language of the Etruscans, who occupied a wealthy civilization in modern-day Tuscany. (The Etruscans inherited the idea of an alphabet from the Greeks, who borrowed it from the Phoenicians.) The first inscriptions in the Latin alphabet date back to the 600s B.C., in a golden brooch and a small pillar.  The Latin alphabet began with 21 letters, excluding G, J, U, Y, and W. The influence of the Greeks, French, Spanish, and Normans in the first millennia and a half of the Christian era brought the alphabet to its current 26 letters, A to Z.
We find one other node for the development of written language in Mesoamerica. The Olmec civilization (1200 B.C. – 400 B.C.) developed the first Mesoamerican writing, upon which the Mayans expounded.  Intricate pictographs, sometimes called “glyphs”, characterize Mesoamerican writing. Rather than administrative purposes, the Mesoamericans used the written language as a status symbol. He who could write could rightfully hold power. 
The written language of the Mesoamericans exhibits exquisite skill and attention to detail, but the Spanish conquest of the region starting in the early 16th century expunged the indigenous writing systems in favor of the Latin alphabet, which native scribes eventually adopted. 
The written language has had a long journey from cuneiform to the alphabet. Today, Earth’s 7+ billion person population speaks over 7,000 living languages, some that have a written form and some that don’t. While perhaps the most difficult subject to teach a child, particularly if one’s language uses a logographic form, developing and learning the written language is integral for the preservation of history and knowledge of a civilization.
Do you know any fun facts about language, English or foreign? Feel free to share in the comments.