What are those white little specs or dots that sometimes form on the finger nail?

What are those white little specs or dots that sometimes form on the finger nail?
My sister told me when I was little those be lies you told.
Usually just style of like a pin bruise...it's when you hit it on something :) But they fade.
Im not sure but i get them adjectives the time when i get my nail done well after i attain my nails done and later take them sour in approaching a while ~~~But all i know is that they grow out and are insanitary at all and arnt a bleak thing!
they are when you dont go and get enouph calcium in your body, YOU NEED MORE CALCIUM
I believe they come from calcium deficiency.
I read somewhere that it indicates zinc deficiency. Here is the intermingle:
http://www.straightdope.com/classics/a3_...
I think its insufficiency of calcium in your diet.
Its when you bump ur finger pin on sumtin, if you carefully survey it over time the white speck will move up toward the end of ur finger fastener, it just grows right rotten. Nothing to worry almost its not serious.