Water supplied by your municipality contains a number of minerals, most of which are deemed to be either beneficial or harmless. However, if your water is considered to be “hard water”, this means that it contains a high concentration of calcium and magnesium, which are not ultimately benign. This elevated concentration may potentially lead to damaged appliances and clogged plumbing.
The workaround for this is to install and utilize a water softener. These units work by extracting the calcium and magnesium from your water via a controlled chemical process. Water softeners can be found in maintenance free forms, which are more expensive, or units that require periodic maintenance but are less costly upfront.
With either option, just remember to accurately consider your water usage and buy a unit that is large enough to sufficiently satisfy your needs.