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When water drops accumulated in the upper atmosphere as clouds fall down on Earth, this is called rain.

There are several types of rain, e.g. drizzle and heavy showers.

If the temperatures are below zero degree Celsius, the water freezes and come down as snow or hail.

When the water in the air does not accumulate at cloud level but close to the ground, or if the observer walks high enough on a mountain to be "inside" the cloud, the surrounding air contains a lot of tiny water droplets that don't fall down but are carried by the wind or air pressure. That's not rain but mist or fog.