(Taken at 30,000 feet in the air.)
Clouds are beautiful. Its hard to really see them from the ground up, but from the sky down, clouds are awesome. They appear to be quiet and fairly still (unless they are conjuring up a storm, of course). Otherwise, they shape and mold themselves and are extremely tranquil. When I have the chance to fly, it is usually at random times of the day or night when I am unable to look out of the window and truly cloud-watch. But a few weeks ago, I had the chance to really see the clouds, flying above them in an airplane. The Sky was blue blue, and the clouds reminded me of waves. So I took a few pictures and I can't stop looking at them. Splendid.
A cloud is a visible mass of droplets of water or frozen crystals suspended in the atmosphere above the surface of the Earth or another planetary body. A cloud is also a visible mass attracted by gravity, such as masses of material in space called interstellar clouds and nebulae. Clouds are studied in the nephology or cloud physics branch of meteorology.
On Earth the condensing substance is typically water vapor, which forms small droplets or ice crystals, typically 0.01 mm (0.00039 in) in diameter. When surrounded by billions of other droplets or crystals they become visible as clouds. Dense deep clouds exhibit a high reflectance (70% to 95%) throughout the visible range of wavelengths.
They thus appear white, at least from the top. Cloud droplets tend to scatter light efficiently, so that the intensity of the solar radiation decreases with depth into the gases, hence the gray or even sometimes dark appearance at the cloud base.
Sources: NASA, ScienceDaily.com