Short answers, pulled from the story.
Precipitation is any product of the condensation of atmospheric water vapor that falls from clouds due to gravitational pull. It includes rain, drizzle, snow, ice pellets, hail, and graupel. Fog and mist are not precipitation because their water vapor does not condense sufficiently to fall.
Approximately 505,000 cubic kilometers of water falls as precipitation each year. Of that total, 398,000 cubic kilometers falls over oceans and 107,000 cubic kilometers over land. The globally averaged annual precipitation is 990 mm, but over land it is only 715 mm.
Guinness World Records lists the world's largest snowflakes as those of January 1887 at Fort Keogh, Montana. One snowflake was allegedly measured at 38 cm wide.
Hailstones can grow to 15 cm in diameter and weigh more than 500 grams. Hail is classified by METAR code GR when stones reach at least 6.4 mm in diameter, a designation derived from the French word grele.
Climate classification systems such as the Koppen climate classification system use average annual rainfall to differentiate between climate regimes. Rain forests require a minimum normal annual rainfall of between 1750 and 2000 mm, while tropical savannas receive between 750 and 1270 mm per year.
Precipitation occurs on Saturn's largest satellite, Titan, where methane falls as a slow drizzle and rain puddles have been observed at its equator and polar regions. On Mars, precipitation most likely takes the form of ice needles when temperatures drop.