Contemporary historyContemporary history, in English-language historiography, is a subset of modern history that describes the historical period from approximately 1945 to the present. Contemporary history is either a subset of the late modern period, or it is one of the three major subsets of modern history, alongside the early modern period and the late modern period. In the social sciences, contemporary history is also continuous with, and related to, the rise of postmodernity.
Topics in prehistoric periodPrehistory, also called pre-literary history, is the period of human history between the first known use of stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5,000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century.
DesertificationDesertification is a type of land degradation in drylands in which biological productivity is lost due to natural processes or induced by human activities whereby fertile areas become arid. It is the spread of arid areas caused by a variety of factors, such as climate change and overexploitation of soil as a result of human activity. Throughout geological history, the development of deserts has occurred naturally. In recent times, the potential influences of human activity, improper land management, deforestation and climate change on desertification is the subject of many scientific investigations.
Regional geographyRegional geography is a major branch of geography. It focuses on the interaction of different cultural and natural geofactors in a specific land or landscape, while its counterpart, systematic geography, concentrates on a specific geofactor at the global level. Attention is paid to unique characteristics of a particular region such as natural elements, human elements, and regionalization which covers the techniques of delineating space into regions.
Topics in infectious diseasesAn infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable disease, is an illness resulting from an infection. Infections can be caused by a wide range of pathogens, most prominently bacteria and viruses. Hosts can fight infections using their immune systems. Mammalian hosts react to infections with an innate response, often involving inflammation, followed by an adaptive response.
Late modern periodIn many periodizations of human history, the late modern period followed the early modern period. It began approximately around the year 1800 and depending on the author, either ended with the beginning of contemporary history after World War II in 1945, or includes the contemporary history period up to the present day. Notable historical events in the late 18th century that marked the transition from the early modern period to the late modern period include – the American Revolution (1765–1791), the French Revolution (1789–1799), and the beginning of the Industrial Revolution around 1760.
Keynesian economicsKeynesian economics (ˈkeɪnziən ; sometimes Keynesianism, named after British economist John Maynard Keynes) are the various macroeconomic theories and models of how aggregate demand (total spending in the economy) strongly influences economic output and inflation. In the Keynesian view, aggregate demand does not necessarily equal the productive capacity of the economy. Instead, it is influenced by a host of factors – sometimes behaving erratically – affecting production, employment, and inflation.
MeteorologyMeteorology is a branch of the atmospheric sciences (which include atmospheric chemistry and physics) with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did not begin until the 18th century. The 19th century saw modest progress in the field after weather observation networks were formed across broad regions. Prior attempts at prediction of weather depended on historical data.
SeismologySeismology (saɪzˈmɒlədʒi,_saɪs-; from Ancient Greek σεισμός (seismós) meaning "earthquake" and -λογία (-logía) meaning "study of") is the scientific study of earthquakes (or generally, quakes) and the propagation of elastic waves through the Earth or other planetary bodies. It also includes studies of earthquake environmental effects such as tsunamis as well as diverse seismic sources such as volcanic, tectonic, glacial, fluvial, oceanic, atmospheric, and artificial processes such as explosions.
CommunismCommunism (from Latin communis) is a left-wing to far-left sociopolitical, philosophical, and economic ideology within the socialist movement, whose goal is the creation of a communist society, a socioeconomic order centered around common ownership of the means of production, distribution, and exchange that allocates products to everyone in the society based on need. A communist society would entail the absence of private property and social classes, and ultimately money and the state (or nation state).