Pearled barley is like white rice — grains have an inedible shell, always removed, and then the next layer is stripped ("pearled") form the barley or rice, but not, say, from brown rice or wheat berry or oat groats. As such, the brown grains are slightly healthier, but take longer to cook. Unpearled barley is almost impossible to find in stores except mixed into birdseed. (For the record, one grain — tef — is sold and milled without the inedible shell removed, since the grains are too small for normal shelling methods to work effectively. When you eat tef, the shell passes through your system without being digested or absorbed.)
Pearled barley should be combined with just under two parts water, by volume, salted, covered, brought to a boil, and simmered on low for 40 minutes. As always, check your grains ten to twenty minutes before time is up, and if the water is gone, remove from heat but keep covered so that grains may steam for the remaining time, whereas if too much water remains, remove the cover and increase the heat.
I'm enjoying my barley tossed with very good olive oil, parmesan cheese, salt, dried thyme, and crushed sumac berry. I highly recommend sumac, thyme, olive oil, and salt, and perhaps toasted sesame seeds, as a tasty dipping for good bread. Completing the meal are Vivaldi and a glass of white wine.