Global warming refers to the phenomenon in which average temperature of our Earth increases. It occurs due to several climatic factors. It is one of the global issue. It is mainly caused by the release of greenhouse effect into atmosphere by transportation, burning and release by industries. These gases increases the overall temperature of Earth. These gases includes carbon dioxide, water vapor, methane, nitrous oxide,etc. Along with increases temperature, it also affect the winds, ocean currents, and other climatic conditions.