Approximately 71% of the Earth's surface is covered by water, including oceans, seas, lakes, rivers, and groundwater.

The Pacific Ocean is the largest and deepest ocean on Earth, covering an area of approximately 165.25 million square kilometers.

The Challenger Deep, located in the Mariana Trench, is the deepest point in the ocean, with a depth of approximately 11,034 meters.

The water cycle, also known as the hydrological cycle, is the continuous movement of water on, above, and below the surface of the Earth.

Evaporation, condensation, precipitation, and infiltration are all major components of the water cycle.

Evaporation is the process by which water changes from a liquid to a gas and enters the atmosphere.

Condensation is the process by which water vapor in the atmosphere condenses into liquid water, forming clouds.

Precipitation is the process by which water falls from the sky in the form of rain, snow, sleet, or hail.

Infiltration is the process by which water seeps into the ground, becoming groundwater.

Groundwater is the largest reservoir of fresh water on Earth, accounting for approximately 99% of all fresh water.

Percolation is the process by which groundwater moves through the ground, seeping from higher elevations to lower elevations.

Transpiration is the process by which water is released from plants into the atmosphere through their leaves.

Glaciation is the process by which water is stored in glaciers and ice caps, forming large masses of ice.

Deglaciation is the process by which glaciers and ice caps melt and release water, contributing to sea level rise.

Purification is the process by which water is cleaned and returned to the atmosphere, removing impurities and contaminants.