A good article on barley by Whole Grains Council explains:

• Pearled barley (also known as pearl barley) is not a whole grain. The article says, "Most of the barley found in they typical supermarket is pearl barley. Although it is technically a refined grain, it's much healthier than other refined grains because (a) some of the bran may still be present, and (b) the fiber in barley is distributed throughout the kernel, and not just in the outer bran layer."
• We should buy "hulled barley". Such barley is sometimes called "dehulled barley" or "hulless barley". This article at DrFuhrman.Com explains:

  "Hulled barley has been minimally processed to remove only the tough inedible outer hull. It is a better choice than pearled barley which receives additional processing and has a lower nutritional value."

• Rolled barley (barley flakes) can be made from either hulled or pearled barley [But how may we find out? Does the nutrition label help us distinguish?]
• Barley flour can also be made from either hulled or pearled barley [But how may we find out? Does the nutrition label help us distinguish?]

See Barley Recipes and BROL Recipes by Dr Greger; BROL stands for Barley, Rye, Oats and Lentils.