1. Freshwater on Earth:
Only about 2.5\% of Earth's water is freshwater, which includes water in rivers, lakes, glaciers, and underground aquifers. The remaining 97.5\% is saltwater found in oceans.
2. Availability of freshwater:
Of the 2.5\% of freshwater, a large portion is locked in glaciers and ice caps, and only a small fraction is available for human use in rivers and lakes.