- Water Cycle : It is the process when the water changes its physical state.
- Fresh water : It is the water found in rivers, lakes, glaciers, groundwater and at the poles.
- Groundwater : It is the water run and is scored under the ground.
- Flow : It is the amount of water it carries
- Basin : It is the area occupied by a river and its tributaries.
- Tributaries : It is smaller rivers flowing into a large river.
- Source : It is the place of a river starts.
- Glaciers : They are masses of ice created by the accumulation of snow.
- Lakes : They are permanent masses of water which have accumulated inland.
- Wadis : They are basins in the desert.
- Rivers : They are permanent currents of water
- Canals : It is build by human beings, and used to transport water.
- Reservoirs : They are artificial lakes to store water.
- Water supply : It is the water in reservoirs and is offered to people and industries.
- Dams : They are build of human beings used to produce electricity.
- Hydroelectric power station : It is a station used to produced electricity through the water.
- Salinity : It is the amount of salt with containing the oceans and seas.
- Warm current : These currents are produced when the temperature of a current is higher than the water around it.
- Cold current : These currents are produced when the temperature of a current is colder than the water around it.
- Tides : They are the diary rise and fall of the water level. They are caused by the gravitational forces of the Moon and the Sun.
- Waves : They are undulations of the surface of the water produced by wind.
- High tide : This tide is produced when rise the level of sea.
- Low tide : This tide is produced when falls the level of sea.
- Lagoons : It is smaller lakes.
- Inland seas : It is a saltwater lake.
- Ocean currents : They are large masses of water, similar to rivers, which circulate through oceans.
- Aquifers : It is forms when the water can´t pass through the impermeable rocks
- Springs : It is forms when groundwater finds a way to the surface. They can be cold or hold water.
- Drinking water : It is the water you can drink. Groundwater is valuable because there are drinking water.
- Icebergs : It is a floating mass of ice.
- Consumption : It is the fresh water which use the human being for life. It is only 0.014%.
- Droughts : It is shortage of water.
- Floods : It is excess of water
- Water Pollution : It is large amount of materials are added to a body of water.
- Acid rain: It contains harmful chemicals such as sulfur and nitrogen. These chemicals are released into the atmosphere as gases.
