The term River It comes from the Latin rius. It is a natural stream of continuous water which flows into a similar one, in a lake or in the sea. When one river flows into another, it is known as tributary.

Each river has a certain flow , which is not usually constant throughout the year. In periods with greater amount of rainfall, the flow increases. On the other hand, when it rains little or they experience high temperature, the flow drops and even in extreme situations the river can dry up.
A river can be: perennial , when the watercourse is located in zones with heavy rains or where there is sufficient water table; seasonal , when it is located in regions where the seasons are very different and the climate is Mediterranean; transient , when it is located in dry or desert climate zones; or allochthonous , when it is in an arid zone and its waters come from other regions rainier
Another possible classification of the river is according to its geomorphology. A river rectilinear It has low sinuosity and has only one channel. A river anastomosed Instead, it has multiple channels and a large capacity of transport and sedimentation. Finally, a river piss It presents high sinuosity and a unique channel.
The longest river in the world is the Amazon , with 6,800 kilometers of extension , followed directly by the Nile , with 6,450 kilometers .
About effluents
According to hydrology, an effluent (also called distributor) is a propagation of water that starts from a river or lake, which can be natural or created by humans. The point at which both currents divide is called confluence, and the flow of the effluent is always less than that of its predecessor. When it comes to a case that occurs in nature, it is mostly born at the mouth of a river, although there are examples of distributors that arise from other points.
It is worth mentioning that the effluent originated by man is more common than the natural one; its objective is usually the disposition of the Water from a river far to a civilization, to irrigate plantations or for personal consumption. Interestingly, although the concept of distributor is opposed to that of tributary, it can be that the same course fulfills both functions, if on the opposite side of its birth it flows into a second river.
Some of the best known effluents are:
* the river Atchafalaya, which flows from the Mississippi, in the US state of Louisiana;
* he Teton, which is also in the United States, and which gives rise to two other distributors, which finally flow into the Henrys Fork River;
* the river Casiquiare, which is born from the high Orinoco, and which represents the most voluminous river on earth that connects two other of great importance, such as the Amazon and the Orinoco;
* the most important effluents of the Rhine River, which are the IJssel, he Waal and the Nederrijn;
* he Tärendö, a Swedish distributor who has his origin in the river Torne and flows in the Kalix;
* the only two effluents of the Nile River, that is, Damietta and Rosetta. Some studies say that in the past it had seven, and all have received their own name, despite not existing today.
Other meaning
Outside of geography, every great abundance of a liquid thing is usually described as a river (“Rivers of ink have been spent to write about the life of the president”) and, by extension, to the abundance of anything else or even people ("A river of people formed in front of the stadium gates").