Data visualization transforms raw data into visual representations—charts, graphs, maps, and diagrams—that reveal patterns, trends, and insights humans can quickly comprehend. It spans fields from journalism and business intelligence to scientific research and public policy, serving as the critical bridge between analysis and action. What makes visualization powerful isn't just aesthetics: it leverages human visual perception, which processes images 60,000 times faster than text, to enable pattern recognition at scale. The key challenge is encoding data into visual channels—position, color, size, shape—in ways that match how our perceptual system works, avoiding misleading representations while maximizing clarity and truth.