What are the different types of salinity?

Salinity can be categorized into several types, including:

1. Seawater Salinity: The average salinity of ocean water, typically around 35 parts per thousand (ppt).
2. Brackish Water Salinity: A mix of freshwater and seawater, with salinity levels between 1 and 30 ppt, commonly found in estuaries.
3. Hypersaline Salinity: Extremely high salinity levels exceeding 40 ppt, often found in evaporation ponds or certain salt lakes.
4. Freshwater Salinity: Water with very low salinity, usually less than 0.5 ppt, typical of rivers and lakes.