Quick sketching is using simple drawings to explore, communicate, and validate ideas visually. It's not fine art; it's functional visualization: stick figures, rectangles, labels. Sketching is a thinking tool for designers, product managers, engineers, and anyone working on ideas. It externalizes thinking, enables rapid iteration, and communicates ideas faster than words. Sketching is foundational to design thinking and innovation: rough ideas sketched, shared, critiqued, and refined in minutes, not days.