Chronology in the context of Periodization

A chronicle (Latin: chronica, from Greek χρονικά chroniká, from χρόνος, chrónos – "time") is a historical account of events arranged in chronological order, as in a timeline. Typically, equal weight is given for historically important events and local events, the purpose being the recording of events that occurred, seen from the perspective of the chronicler. A chronicle which traces world history is a universal chronicle. This is in contrast to a narrative or history, in which an author chooses events to interpret and analyze and excludes those the author does not consider important or relevant.

The information sources for chronicles vary. Some are written from the chronicler's direct knowledge, others from witnesses or participants in events, still others are accounts passed down from generation to generation by oral tradition. Some used written material, such as charters, letters, and earlier chronicles. Still others are tales of unknown origin that have mythical status. Copyists also changed chronicles in creative copying, making corrections or in updating or continuing a chronicle with information not available to the original chronicler. Determining the reliability of particular chronicles is important to historians.

Eratosthenes of Cyrene (/ɛrəˈtɒsθəniːz/; Ancient Greek: Ἐρατοσθένης [eratostʰénɛːs]; c. 276 BC – c. 195/194 BC) was an Ancient Greek philosopher, polymath and scholar. He was known as a mathematician, geographer, poet, astronomer, and music theorist. Eratosthenes became the chief librarian at the Library of Alexandria. His work was the precursor to the modern discipline of geography, and he introduced some of its terminology, coining the terms geography and geographer.

He is best remembered as the first known person to calculate the Earth's circumference. He was also the first to calculate Earth's axial tilt, which similarly proved to have remarkable accuracy. He created the first global projection of the world incorporating parallels and meridians based on the available geographic knowledge of his era. Eratosthenes was the founder of scientific chronology; he used Egyptian and Persian records to estimate the dates of the main events of the Trojan War, dating the sack of Troy to 1184 BC. In number theory, he introduced the sieve of Eratosthenes, an efficient method of identifying prime numbers and composite numbers.

An anachronism (from the Greek ἀνά ana, 'against' and χρόνος khronos, 'time') is a chronological inconsistency in some arrangement, especially a juxtaposition of people, events, objects, language terms and customs from different time periods. The most common type of anachronism is an object misplaced in time, but it may be a verbal expression, a technology, a philosophical idea, a musical style, a material, a plant or animal, a custom, or anything else associated with a particular period that is placed outside its proper temporal domain.

An anachronism may be either intentional or unintentional. Intentional anachronisms may be introduced into a literary or artistic work to help a contemporary audience engage more readily with a historical period. Anachronism can also be used intentionally for purposes of rhetoric, propaganda, comedy, or shock. Unintentional anachronisms may occur when a writer, artist, or performer is unaware of differences in technology, terminology and language, customs and attitudes, or even fashions between different historical periods and eras.

The Conventional Egyptian chronology reflects the broad scholarly consensus about the outline and many details of the chronology of Ancient Egypt. It places the beginning of the Old Kingdom in the 27th century BC, the beginning of the Middle Kingdom in the 21st century BC and the beginning of the New Kingdom in the mid-16th century BC.

Disagreements remain within this consensus, and various chronologies diverge by about 300 years for the Early Dynastic Period, up to 30 years in the New Kingdom, and a few years in the Late Period.

A timeline is a list of events displayed in chronological order. It is typically a graphic design showing a long bar labelled with dates paralleling it, and usually contemporaneous events.

Timelines can use any suitable scale representing time, suiting the subject and data; many use a linear scale, in which a unit of distance is equal to a set amount of time. This timescale is dependent on the events in the timeline. A timeline of evolution can be over millions of years, whereas a timeline for the day of the September 11 attacks can take place over minutes, and that of an explosion over milliseconds. While many timelines use a linear timescale—especially where very large or small timespans are relevant -- logarithmic timelines entail a logarithmic scale of time; some "hurry up and wait" chronologies are depicted with zoom lens metaphors.

Annals (Latin: annāles, from annus, "year") are a concise historical record in which events are arranged chronologically, year by year, although the term is also used loosely for any historical record.

In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured.

The moment of epoch is usually decided by congruity, or by following conventions understood from the epoch in question. The epoch moment or date is usually defined from a specific, clear event of change, an epoch event. In a more gradual change, a deciding moment is chosen when the epoch criterion was reached.

Change and continuity is a classic dichotomy within the fields of history, historical sociology, and the social sciences more broadly. The question of change and continuity is considered a classic discussion in the study of historical developments. The dichotomy is used to discuss and evaluate the extent to which a historical development or event represents a decisive historical change or whether a situation remains largely unchanged. A good example of this discussion is the question of how much the Peace of Westphalia in 1648 represents an important change in European history. In a similar vein, historian Richard Kirkendall once questioned whether FDR's New Deal represented "a radical innovation or a continuation of earlier themes in American life?" and posed the question of whether "historical interpretations of the New Deal [should] stress change or emphasize continuity?" The issue here is if the New Deal marks something radically new (change) in US history or if the New Deal can be understood as a continuation (continuity) of tendencies in American history that were in place well before the 1930.

The dichotomy is important in relation to constructing, discussing, and evaluating historical periodizations. In terms of creating and discussing periodization (e.g. the Enlightenment or the Victorian Era,) the dichotomy can be used to assess when a period can be said to start and end, thus making the dichotomy important in relation to understanding historical chronology. Economic historian Alexander Gerschenkron has taken issue with the dichotomy, arguing that continuity "appears to mean no more than absence of change, i.e. stability." German historian Reinhart Koselleck, however, has been said to challenge this dichotomy.

This timeline of cosmological theories and discoveries is a chronological record of the development of humanity's understanding of the cosmos over the last two-plus millennia. Modern cosmological ideas follow the development of the scientific discipline of physical cosmology.

For millennia, what today is known to be the Solar System was regarded as the contents of the "whole universe", so advances in the knowledge of both mostly paralleled. Clear distinction was not made until circa mid-17th century. See Timeline of Solar System astronomy for further details on this side.

Uruk, the archeological site known today as Warka, was an ancient city in the Near East or West Asia, located east of the current bed of the Euphrates River, on an ancient, now-dried channel of the river in Muthanna Governorate, Iraq. The site lies 93 kilometers (58 miles) northwest of ancient Ur, 108 kilometers (67 miles) southeast of ancient Nippur, and 24 kilometers (15 miles) northwest of ancient Larsa. It is 30 km (19 mi) east of modern Samawah.

Uruk is the type site for the Uruk period. Uruk played a leading role in the early urbanization of Sumer in the mid-4th millennium BC.By the final phase of the Uruk period around 3100 BC, the city may have had 40,000 residents, with 80,000–90,000 people living in its environs, making it the largest urban area in the world at the time. Gilgamesh, according to the chronology presented in the Sumerian King List (SKL), ruled Uruk in the 27th century BC. After the end of the Early Dynastic period, with the rise of the Akkadian Empire, the city lost its prime importance. It had periods of florescence during the Isin-Larsa period, Neo-Assyrian and Neo-Babylonian periods and throughout the Achaemenid (550–330 BC), Seleucid (312–63 BC) and Parthian (227 BC to AD 224) periods, until it was finally abandoned shortly before or after the Islamic conquest of 633–638.

The Parian Chronicle or Parian Marble (Latin: Marmor Parium, abbr. Mar. Par.) is a Greek chronology, covering the years from 1582 BC to 299 BC, inscribed on a stele. Found on the island of Paros in two sections, and sold in Smyrna in the early 17th century to an agent for Thomas Howard, Earl of Arundel, this inscription was deciphered by John Selden and published among the Arundel Marbles, Marmora Arundelliana (London 1628–9) nos. 1–14, 59–119. The first of the sections published by Selden has subsequently disappeared. A further third fragment of this inscription, comprising the base of the stele and containing the end of the text, was found on Paros in 1897. It has entries from 336/35 to 299/98 BC.

The two known upper fragments, brought to London in 1627 and presented to Oxford University in 1667, include entries for the years 1582/81–355/54 BC. The surviving upper chronicle fragment currently resides in the Ashmolean Museum at Oxford. It combines dates for events which modern readers would consider mythic, such as the Flood of Deucalion (equivalent to 1529/28 BC) with dates we would categorize as historic. For the Greeks, the events of their distant past, such as the Trojan War (dated from 1217 to 1208 BC in the Parian inscription) and the Voyage of the Argonauts were historic: their myths were understood as legends to the Greeks. In fact the Parian inscriptions spend more detail on the Heroic Age than on certifiably historic events closer to the date the stele was inscribed and erected, apparently during 264/263 BC. "The Parian Marble uses chronological specificity as a guarantee of truth," Peter Green observed in the introduction to his annotated translation of the Argonautica of Apollonios Rhodios: "the mythic past was rooted in historical time, its legends treated as fact, its heroic protagonists seen as links between the 'age of origins' and the mortal, everyday world that succeeded it."

An era is a span of time defined for the purposes of chronology or historiography, as in the regnal eras in the history of a given monarchy, a calendar era used for a given calendar, or the geological eras defined for the history of Earth.

Comparable terms are Epoch, age, period, saeculum, aeon (Greek aion) and yuga (Sanskrit युग).

The chronology of the ancient Near East is a framework of dates for various events, rulers and dynasties. Historical inscriptions and texts customarily record events in terms of a succession of officials or rulers: "in the year X of king Y". Comparing many records pieces together a relative chronology relating dates in cities over a wide area.

For the 3rd and 2nd millennia BC, this correlation is less certain but the following periods can be distinguished:

Chronological dating, or simply dating, is the process of attributing to an object or event a date in the past, allowing such object or event to be located in a previously established chronology. This usually requires what is commonly known as a "dating method". Several dating methods exist, depending on different criteria and techniques, and some very well known examples of disciplines using such techniques are, for example, history, geology, paleontology, archaeology, astronomy and even forensic science, since in the latter it is sometimes necessary to investigate the moment in the past during which the death of a cadaver occurred. These methods are typically identified as absolute, which involves a specified date or date range, or relative, which refers to dating which places artifacts or events on a timeline relative to other events and/or artifacts. Other markers can help place an artifact or event in a chronology, such as nearby writings and stratigraphic markers.

Absolute dating is the process of determining an age on a specified chronology in archaeology and geology. Some scientists prefer the terms chronometric or calendar dating, as the use of the word "absolute" implies an unwarranted certainty of accuracy. Absolute dating provides a numerical age or range, in contrast with relative dating, which places events in order without any measure of the age between events.

In archaeology, absolute dating is usually based on the physical, chemical, and life properties of the materials of artifacts, buildings, or other items that have been modified by humans and by historical associations with materials with known dates (such as coins and historical records). For example, coins found in excavations may have their production date written on them, or there may be written records describing the coin and when it was used, allowing the site to be associated with a particular calendar year. Absolute dating techniques include radiocarbon dating of wood or bones, potassium-argon dating, and trapped-charge dating methods such as thermoluminescence dating of glazed ceramics.