hi chellam please refer difference between Coal & lignite

Coal is a readily combustible black or brownish-black sedimentary rock. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure. Coal, a fossil fuel, is the largest source of energy for the generation of electricity worldwide, as well as one of the largest worldwide source of carbon dioxide emissions. Gross carbon dioxide emissions from coal usage are slightly more than those from petroleum and about double the amount from natural gas.Coal is extracted from the ground by mining, either underground or in open pits.



Lignite, often referred to as brown coal, or Rosebud coal by Northern Pacific Railroad, is a soft brown fuel with characteristics that put it somewhere between coal and peat. It is considered the lowest rank of coal; it is primarily mined in Russia, the United States, Australia and many European countries, and it is used almost exclusively as a fuel for steam-electric power generation. Lignite is brownish-black in color and has a carbon content of around 60%, Lignite has a high content of volatile matter which makes it easier to convert into gas and liquid petroleum products than higher ranking coals. However, its high moisture content and susceptibility to spontaneous combustion can cause problems in transportation and storage.
Because of its low energy density, brown coal is inefficient to transport and is not traded extensively on the world market compared with higher coal grades.