Hard water contains calcium and magnesium, it is better to drink and taste than soft water. Soft water is salty in taste because it contains sodium. Groundwater like deep wells is an example of hard water. Rain water is an example of soft water.
If you get more information about hard water vs soft water then visit https://swiftgreenfilters.com/blogs/water-filters/hard-water-vs-soft-water-difference-between-hard-and-soft-water