Nowadays, it is thought by some people that English, which is now the most spoken language in the world, may one day predominate over all the other languages, eventually resulting their disappearance. However, this result has some advantages like elevation in the understanding among countries and increase in their economic growth. On the other hand, it also has some disadvantages like disappearing of all the other languages and collapse of tourism. This essay will discuss the advantages and disadvantages of having one language in the world.