"What a pretty design!" we often say while refering to patterns, pictures or objects. We use the term almost interchangeably with "drawing", "sketch" or "art". While generally its passable, technically these are all different terms.
Drawing, as you already understand from the previous lesson, is a skill set.
Design on the other hand is much more. Designers look more aspects than making a pretty drawing. They think about the future, fashion, understand the markets and trends,materials & techniques, work with inspirations and then come up with a collection which is a sum total of thier research as well as aesthetically appealing>pretty!
But both are inseparable. While Designing requires the skill of drawing, drawing reaches its fulfillment through design. Ultimately drawing aspires towards being Art.