There is no milk.  It is made from raw creamnfrom a cow.

Milk comes from spinning(typically) raw cream in order to separate the cream from the milk and reduce the fat content and solids present.

A separated Cream is left, with varying fat contents, hence heavy cream, light cream, etc ...

And of course the milk is left, depending on milkfat level that was separated.

Butter is made from heavy cream by churning it until the water/buttermilk is separated from the fat solids.

So to recap:

Raw Cow Cream(milk but not really) gets you:

Milk
Cream
Butter
Butter Milk


I don't see how you can even maybe a normal butter with milk.  Wouldn't have enough fat I wouldn't think
 Maybe on industrial scale and additives, not sure?  

 To clarify, a cow technically produces milk, but it is milk that resembles nothing like what we have today and know as milk. Cream is the closer comparison.  


Apparently this is also regional too. No idea.