Among the most critical issues, facing the world is Global warming. Remember, that eventful summer a decade ago, it was much comfortable than the present one. Especially the summers of Britain have got a drastic change. They are no longer found to be cozy and comfortable. This has compelled people to go for air conditioners. Just the day before yesterday, you visited your maternal brother at his office. You noticed a series of air conditioning machines to hold the men and machines cool. But you may just two years when you went there was hardly more than two air conditioners, now it is nearly half a dozen machines are keeping that same area cool.