Drugs continue to play critical roles in the maintenance of normal body functions. This is the thrust behind the ongoing search for the development of effective and cost-effective drugs. Conventionally, drug discovery processes have involved studies on natural products and chemical synthesis to yield therapeutic formulations with commercial application. This process develops at a tremendous cost for a long time. Over the past few decades, computer technology has been used in drug discovery. This has led to improved understanding of the quantitative relationship between molecular structure and biological activity. In addition, greater understanding of the complex biological processes provided by progress in bioinformatics and genomics also contributes to drug discovery by promoting goal validation and data integration. New generation software or tools are now available in computer-aided drug discovery and they have contributed to shortening the drug design and discovery cycles with desired reduction in cost. This chapter discusses the pharmacological processes and the effects of information and communication technology and explains some of the main tools used in silico studies. Detailed protocols of these approaches are not covered.