Coal is the primary source of energy for most of the countries in the world. Although the main use of coal is in the generation of electricity, recently synthesis of liquid fuel from coal is becoming attractive, although coal liquefaction is a very old and well known process that was developed just after World War I. This may relieve pressure on petroleum as the only source of automobile fuel. However, a major concern in the use of coal is emissions of various pollutants including gases that cause acid rain and CO₂ emissions — a major contributor to global warming. Two approaches are pursued to reduce emissions from coal power plants. Most of the recent coal power plants are designed to produce supercritical steam, increasing the efficiency to about 50%. Another approach is to develop zero emission coal power plants. In this chapter, a comprehensive discussion on the use of coal and associated issues are presented.