A 3-dimensional, interactive, animated nonlinear tutorial on the structure of DNA. The user can choose among several views and/or display the various components of the DNA molecule in 3-D! Illustrates the double helix, hydrogen bonds, base pairing. Zooms in to single base pairs. Animations simulate replication, identify codons, complementary mRNA sequences, and amino acids coded for. Also highlighted: backbone traces, antiparallel strands, 5' and 3' ends. Quiz questions for students are provided, gaged to ages 14+, 18+, and 20+, along with lesson plans for teachers. Available at DNA.MolviZ.Org.