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Those people who believe we are not alone in this world say that there are other living creatures in the universe and a day will come when they visit us, but, people have already been in the space and they have seen those planets and stars and the whole celestial stuff and they haven’t seen any living creatures there. Moreover, we know now that Earth is the only planet appropriate for living. There is air to breathe and water to drink and so on. But there is no air on other plants and so there is nothing to breathe with. But, it is possible that those strange creatures breathe with something else but not air. They call those creatures Martians and according to movies they always come from Mars, but science says that there is no life on Mars. So, why provided with the whole knowledge about universe people still believe they are not alone and there are other living creatures in the universe and they keep calling them Martians? If there is another form of life in this world than where this form is and where they live and what they breathe with?