This chapter provides an overview of the chemical basis of life—the design for life—as revealed by molecular biology. It focuses on three topics: cells; the chemical composition of deoxyribonucleic acid (DNA) and its structure; and how organisms create proteins. DNA, the genetic text which spells out the recipe for life—the instructions on how to make each species—consists of four chemicals known as base pairs. As the individual units of information that give each cell its specific biochemical instructions, genes are made of small molecules of DNA like beads on a string. The packet of information present along a DNA molecule, a gene, determines the one-dimensional sequence of amino acids. The protein formation process begins with the transcription of the DNA contained in the cell's nucleus. The basic living unit of biolife is the cell. The chapter concludes with a brief discussion on the biotechnology revolution resulting from this new knowledge.