One of the essential factors shaping the Earth's surface and maintaining the life that has de�veloped there is water. Water has a significant influence on the safety of human activity as well. The source of the surface water is mainly rainfall. Measuring the amount of rain has been an important issue for millennia and has become a scientifically based activity in the last few centuries. In the recent period, several methods have been developed for measuring and detecting precipitation and precipitation intensity, which provide data at different levels of accuracy. In addition to meteorologists and hydrolo�gists, many disciplines use precipitation data included in professional publications without evaluating their accuracy. To evaluate the accuracy of precipitation data originating from a certain data source, the user needs to know its accuracy category and reliability. This article serves this purpose by presenting the rainfall measurement procedures from traditional catching measurements to radar, from satellitebased remote sensing to acoustic measurements, and estimation based on lightning statistics. It also presents the described procedures in tabular form, through which the user of the precipitation data can get an idea of the applied data’s accuracy.