Precipitation denotes any kind of hydrometeors reaching Earth’s surface, including drizzle, rain, snow, graupel, and hail. This chapter first discusses common raindrop and snowflake size distributions, like the Marshall–Palmer size distribution. It also presents an overview of observed precipitation rates, measured with rain gauges at Earth’s surface. We explain how estimates of precipitation rates can be obtained from radar measurements and how different types of radar scans and images can be interpreted to classify precipitation into stratiform and convective precipitation, from measurements of radar reflectivity and Doppler velocity. By doing so, we connect the knowledge on microphysical processes in warm and cold clouds from previous chapters with macroscopic cloud properties retrieved by radar. Moreover, this chapter discusses how precipitation can originate in frontal systems, via orographic lifting of moist air masses or other mechanisms. This chapter also discusses the geographical distribution of precipitation in the present climate, how it has changed since the 1950s, and how it is projected to change until the end of this century. Finally, extreme precipitation and artificial weather modification are introduced.