A river is a natural flowing watercourse freshwater, flowing towards an ocean, lake or another river. In some cases a river flows into the ground and becomes dry at the end of its course without reaching another body of water. Small rivers can be referred to using names such as stream, brook and rill. There are no official definitions for the generic term river as applied to geographic features, although in some countries or communities a stream is defined by its size. Many names for small rivers are specific to geographic location. Sometimes a river is defined as being larger than a creek, but not always: the language is vague. Rivers are part of the hydrological cycle. Water collects in a river from precipitation through a drainage basin from surface runoff and other sources such as groundwater recharge and the release of stored water in natural ice and snowpacks. Rivers and streams are considered major features within a landscape, they only cover around 0.1% of the land on Earth. They are made more obvious and significant to humans by the fact that many human cities and civilizations are built around the freshwater supplied by rivers and streams.
Most of the major cities of the world are situated on the banks of rivers, as they are, or were, used as a source of water, for obtaining food, for transport, as borders, as a defensive measure, as a source of hydropower to drive machinery, for bathing, as a means of disposing of waste. Potamology is the scientific study of rivers, while limnology is the study of inland waters in general. A river begins at a source, follows a path called a course, ends at a mouth or mouths; the water in a river is confined to a channel, made up of a stream bed between banks. In larger rivers there is also a wider floodplain shaped by flood-waters over-topping the channel. Floodplains may be wide in relation to the size of the river channel; this distinction between river channel and floodplain can be blurred in urban areas where the floodplain of a river channel can become developed by housing and industry. Rivers can flow down mountains, through valleys or along plains, can create canyons or gorges; the term upriver refers to the direction towards the source of the river, i.e. against the direction of flow.
The term downriver describes the direction towards the mouth of the river, in which the current flows. The term left bank refers to the left bank in the direction of right bank to the right; the river channel contains a single stream of water, but some rivers flow as several interconnecting streams of water, producing a braided river. Extensive braided rivers are now found in only a few regions worldwide, such as the South Island of New Zealand, they occur on peneplains and some of the larger river deltas. Anastamosing rivers are quite rare, they have multiple sinuous channels carrying large volumes of sediment. There are rare cases of river bifurcation in which a river divides and the resultant flows ending in different seas. An example is the bifurcation of Nerodime River in Kosovo. A river flowing in its channel is a source of energy which acts on the river channel to change its shape and form. In 1757, the German hydrologist Albert Brahms empirically observed that the submerged weight of objects that may be carried away by a river is proportional to the sixth power of the river flow speed.
This formulation is sometimes called Airy's law. Thus, if the speed of flow is doubled, the flow would dislodge objects with 64 times as much submerged weight. In mountainous torrential zones this can be seen as erosion channels through hard rocks and the creation of sands and gravels from the destruction of larger rocks. A river valley, created from a U-shaped glaciated valley, can easily be identified by the V-shaped channel that it has carved. In the middle reaches where a river flows over flatter land, meanders may form through erosion of the river banks and deposition on the inside of bends. Sometimes the river will cut off a loop, shortening the channel and forming an oxbow lake or billabong. Rivers that carry large amounts of sediment may develop conspicuous deltas at their mouths. Rivers whose mouths are in saline tidal waters may form estuaries. Throughout the course of the river, the total volume of water transported downstream will be a combination of the free water flow together with a substantial volume flowing through sub-surface rocks and gravels that underlie the river and its floodplain.
For many rivers in large valleys, this unseen component of flow may exceed the visible flow. Most but not all rivers flow on the surface. Subterranean rivers flow underground in caverns; such rivers are found in regions with limestone geologic formations. Subglacial streams are the braided rivers that flow at the beds of glaciers and ice sheets, permitting meltwater to be discharged at the front of the glacier; because of the gradient in pressure due to the overlying weight of the glacier, such streams can flow uphill. An intermittent river only flows and can be dry for several years at a time; these rivers are found in regions with limited or variable rainfall, or can occur because of geologic conditions such as a permeable river bed. Some ephemeral rivers flow during the summer months but not in the winter; such rivers are fed from chalk aquifers which recharge from winter rainfall. In England these rivers are
The United States Football League was an American football league that played for three seasons, 1983 through 1985. The league played a spring/summer schedule in each of its active seasons; the 1986 season was scheduled to be played in the autumn/winter, directly competing against the long-established National Football League. However, the USFL ceased operations; the ideas behind the USFL were conceived in 1965 by New Orleans businessman David Dixon, who saw a market for a professional football league that would play in the summer, when the National Football League and college football were in their off-season. Dixon had been a key player in the construction of the Louisiana Superdome and the expansion of the NFL into New Orleans in 1967, he developed "The Dixon Plan"—a blueprint for the USFL based upon securing NFL-caliber stadiums in top TV markets, securing a national TV broadcast contract, controlling spending—and found investors willing to buy in. Though the original franchise owners and founders of the USFL had promised to abide by the general guidelines set out by Dixon's plan, problems arose before the teams took the field, with some franchises facing financial problems and instability from the beginning.
Due to pressure from the NFL, some franchises had difficulty securing leases in stadiums that were used by NFL teams, forcing them to scramble to find alternate venues in their chosen city or hurriedly move to a new market. The USFL had no hard salary cap, because of this, some teams escalated player payrolls to unsustainable levels despite pledges to keep costs under control. While a handful of USFL franchises abided by the Dixon Plan and were stable, others suffered repeated financial crises, there were many franchise relocations and ownership changes during the league's short existence; these problems were worsened as some owners began engaging in bidding wars for star players against NFL teams and each other, forcing other owners to do the same or face a competitive disadvantage. On the field, the USFL was regarded as a good product. Many coaches and team executives had NFL experience, many future top NFL players and coaches got their start in the new league, including several who were inducted into the Pro Football Hall of Fame and/or the College Football Hall of Fame.
The Michigan Panthers won the first USFL championship in 1983. The Philadelphia Stars won the second USFL championship in 1984, after relocating to Baltimore, won the final USFL championship in 1985 as the Baltimore Stars in what was a rematch of the first USFL title game. In 1985, the USFL voted to move from a spring to a fall schedule in 1986 to compete directly with the NFL; this was done at the urging of New Jersey Generals majority owner Donald Trump and a handful of other owners as a way to force a merger between the leagues. As part of this strategy, the USFL filed an antitrust lawsuit against the National Football League in 1986, a jury ruled that the NFL had violated anti-monopoly laws. However, in a victory in name only, the USFL was awarded a judgment of just $1, which under antitrust laws, was tripled to $3; this court decision ended the USFL's existence. The league never played its planned 1986 season, by the time it folded, it had lost over US$163 million; the USFL is significant in part for the level of talent that played in the league.
The league was noteworthy for signing three consecutive Heisman Trophy winners: Georgia running back Herschel Walker and Boston College quarterback Doug Flutie signed with the New Jersey Generals, Nebraska running back Mike Rozier signed with the Pittsburgh Maulers out of college as did numerous other collegiate stars. Future Pro Football Hall of Fame members defensive end Reggie White of the University of Tennessee, offensive tackle Gary Zimmerman and quarterbacks Jim Kelly of the University of Miami and Steve Young of Brigham Young University, began their professional careers with the USFL's Memphis Showboats, Los Angeles Express, Houston Gamblers, Los Angeles Express, respectively. A number of NFL veterans of all talent levels played in the USFL, it is true that some NFL backups such as quarterbacks Chuck Fusina and Cliff Stoudt, G Buddy Aydelette, WR Jim Smith who had limited success in the NFL became major stars in the USFL. However, many NFL backups struggled or did not make it in the USFL.
Additionally, the USFL lured in NFL starters, including a handful of stars in the primes of their careers, including the 1980 NFL MVP, Cleveland Browns' quarterback Brian Sipe, the Buffalo Bills' three-time pro bowl running back Joe Cribbs, the Kansas City Chiefs' three-time pro bowl safety Gary Barbaro. For many decades after its inception, American football was regarded as a second-tier sport behind baseball, long-regarded as America's national pastime; as a result, the elite levels of American football lacked the financial wherewithal to finance their own facilities and instead played in ballparks hastily re-purposed for football. However, since gridiron football in particular is responsible for excessive wear and tear on a grass playing field, baseball clubs were not keen to see football played in their parks throughout the entire baseball season. Thus, the need to use ballparks played a large part in ensuring that the National Football League and early rivals would delay the start of their seasons until September when the baseball season was winding down, thus affording baseball teams the exclusive use of their facilities in the spring and summer.
Starting in the 1950s, a number of technological changes and trends caused
Development or developing may refer to: Business development, a process of growing a business Career development Corporate development, a position in a business Energy development, activities concentrated on obtaining energy from natural resources Green development, a real estate concept that considers social and environmental impact of development Land development, altering the landscape in any number of ways Land development bank, a kind of bank in India Leadership development New product development Organization development Professional development Real estate development Research and development Training and development Fundraising called "development" Child development, between birth and the end of adolescence Development, an academic journal in developmental biology Developmental biology, the study of the process by which organisms grow and develop Developmental psychology, the scientific study of how and why human beings change over the course of their life Drug development, the entire process of bringing a new drug or device to the market Embryogenesis, or development, the process by which the embryo is formed Human development, the process of growing to maturity Neural development, the processes that generate and reshape the nervous system Personal development, or self-help Prenatal development, the process in which a human embryo or fetus gestates during pregnancy Tooth development or odontogenesis Youth development Artificial development, an area of computer science and engineering Software development, the development of a software product Web development, work involved in developing a web site Mobile app development, act or process by which a mobile app is developed Development, a 2002 album by Nonpoint Development hell, when a project is stuck in development Filmmaking, development phase, including finance and budgeting Musical development, a compositional process Photographic development Video game development Community development, practices to improve various aspects of communities Development communication Developing country, a nation with a less developed industrial base Development aid, financial aid given by governments and other agencies Development geography, a branch of geography which refers to the standard of living and quality of life of inhabitants Development studies, most taught and researched in the third world and in countries with a colonial history Development theory Economic development, the process by which a nation improves the economic and social well-being of its people European Development Fund, the main instrument for European Union aid for development Human Development Index, used to rank countries by level of human development Human development, the science that seeks to understand how and why people of all ages and circumstances change or remain the same over time International development level of economic development Regional development and assistance to regions which are less economically developed Rural development, the process of improving the quality of life and economic well-being of people living in rural areas Sociocultural evolution, how cultures and societies have changed over time Sustainable development Development, rolling one smooth surface over another Development, a countable collection of open coverings Development, a term used in chess Development of doctrine, a term used by John Henry Newman to describe Catholic teachings Driver development program, a program used by racing teams to develop younger drivers