I have had these small, raised brown spots on my hand too. They have the diameter of a small pin or needle, but are noticeable because they appear in clusters. They appear on the palm area, around the fingers. Usually 20-30 on one hand, and a few on the other.
I have had this condition for years. I used to smoke, and I thought they were nicotine spots. But I quit more than 6 months ago, and they still come. They appear, and then they disappear, then reappear, sometimes in different places.
I sometimes use an exacto blade and simply slice them off - they are not very deep into the skin, I mean if you tried to just cut it off it only 1 or 2 layers deep, it does not bleed. They sometimes appear with tiny bubbles nearby which are not white, but which contain clear fluid (I don't slice those anymore!).
I wonder what these are, too. Surprised to see a few people report this but no answers. I only found this, like others, because I was searching to see what they were, so I described them hoping future searchers would find the same result - maybe someone will reply... or I guess I am off to the dermatologist.