1. Surface Water: This includes rivers, lakes, streams, and wetlands. It's water that's found on the Earth's surface.

2. Groundwater: Water that exists beneath the Earth's surface in soil and rock formations. This is a vital source of drinking water for many communities.

3. Glaciers and Ice Caps: Large masses of frozen water that store a significant amount of the Earth's freshwater. They are melting at an alarming rate due to climate change.

4. Soil Moisture: Water held within the soil, absorbed from precipitation and other sources. This is important for plant growth.