This document provides an introduction to data visualization techniques including 2D scalar fields, quantitative vs qualitative representations, isocontours, marching cubes, direct volume rendering, transfer functions, vector fields visualization using streamlines and line integral convolution, and visualizing hierarchical, map, and social data. It discusses principles for representing ordered data with colors and representing different levels with different colors. It also covers speeding up techniques like octrees and extrema graphs and handling multiple data layers.