An eyeshadow palette offers a spectrum of shades, usually within the same color group, or at least in complementary shades. At one end of the spectrum will be lighter shades (to highlight and brighten) then medium shades (for base shades on lids) then dark shades (for lining and defining). Sometimes they'll have a mix of finishes, offering a blend of sheers and shimmers, sometimes an accent color for fun. Every palette is different and you should just go with your gut instinct in picking which one you think you’ll use most.
