White spots on calves and inside of arms

Hey guys,
I have these white spots on my calves and the inside part of my arm.  They sometime also appear on the front part of my arm but are not quite as visible.  They do not itch, hurt, and are not bumps but I have noticed my skin is usually cold is the places I get them.  Also they go away on my arms if I raise my arms above my head but when brought back down they reappear.  I have had them since middle school and am now in college.  My brother who is in high school has the same exact thing that I have.  I have also attached a picture.  Any help is appreciated.

[maatson]

Bier spots.

[eharmon]

Wow thanks for that quick reply.  I read about it and that is exactly what I have.  I wish I would've posted this question years ago instead of wasting all that time searching for it.

[maatson]

All difficult things have their origin in which  easy and simple are hidden .-Lao Tzu