Fusha is also known as Classical Arabic. This is the actual Arabic used in writing books, newspapers etc. Fusha is taught in every Arabic School in the Arab world, but is not the spoken language. It is only for reading purposes as well as listening purposes as well as to the NEWS or any of its equivalence. On the other hand, to overcome any misunderstanding that may occur among Arabs due to different dialects; a one unified language or dialect is used in order for every Arab to understand, from the Gulf and all the way to Morocco. I would like to use an example to make it easier to understand; the phrase "how are you" is different in every Arabic country than that, as well, to Fusha. How are you in Fusha is : Kaif halok? (the example used is if speaking to a guy) But in every Arab country it is different for example: The Gulf region they would say: Shlonak? Palestine, Syria, Jordan, Lebanon: Keefak or shoo akhbarak? Egypt: Ezzayak? Morocco: Kidayer? Not all Arabs are familiar with every dialect, so a unified language is used and all Arabs would understand. In other words, all Arabs will understand "kaif halak?" but necessarily understand it from a different dialect than the one they speak. Last but not least, the Fusha is the Arabic used in the Holy Quran, the holy book of Muslims, and that most of the Arabs are Muslims - they are obliged to understand Fusha for that very reason. I hope this may have answered your answer. If you may need any further understanding or so, please dont hesitate to let me know and tell me about your enquiries.