Answer:
It is by nature, soft as silk; A puffy cloud, white as milk; Snow tops this tropical crop; The dirtiest part of a mop
Has feathers but can't fly. Rests on legs but can't walk.
I am black when I am clean and white when I am dirty?
Dies half its life. Lives the rest. Dances without music. Breathes without breath.
It is the electronic version of junk mail or a salty meat in a can.
If it’s information you seek, come and see me. If it’s pairs of letters you need, I have consecutively three. What am I?