The expressions Arabic and Classical Arabic usually refer to the pure Arabic language which is, according to Arabic speakers, both the language of present-day media across North Africa and the Middle East (from Morocco to Iraq) and the language of the Qur'an. The expression media includes not only television, radio, newspapers and magazines, but also all written matter, including all books, documents of every kind, and reading primers for small children.
The term Modern Standard Arabic is sometimes used in the West to refer to the language of the media as opposed to the language of "classical" Arabic literature; Arabs make no such distinction, and regard the two as identical. The word "Arabic" also refers to the many national or regional dialects/languages derived from Classical Arabic, spoken daily across North Africa and the Middle East, which sometimes differ enough to be mutually incomprehensible. These dialects are not frequently written, although a certain amount of literature (particularly plays and poetry) exists in many of them, notably Lebanon and Egypt.
It is sometimes difficult to translate Islamic concepts, and concepts specific to Arab culture, without using the original Arabic terminology. The Qur'an is expressed in Arabic and traditionally Muslims deem it impossible to translate in a way that would adequately reflect its exact meaning - indeed, until recently, some schools of thought maintained that it should not be translated at all. A list of Islamic terms in Arabic covers those terms which are too specific to translate in one phrase. While Arabic is strongly associated with Islam (and is the language of salat), it is also spoken by Arab Christians, Oriental Jews, and indeed Iraqi Mandaeans; and, of course, the vast majority of the world's Muslims do not actually speak it; they only know some fixed phrases of Arabic, as used in Islamic prayer.
The English word algorithm is derived from the name of the inventor of algebra - an Arabic word like alchemy, alcohol, azimuth, nadir, and zenith. See a List of English words of Arabic origin. Arabic numerals are what we use in English - but, except in some North African countries, modern Arabs generally use what they call "Hindi numerals". Spanish is the European language with the most borrowings from Arabic.
Arabic is a Semitic language, fairly closely related to, for instance, the Hebrew language and the Aramaic language. Many dialects are spoken in modern Arabic states such as Egypt, Lebanon, and Morocco, but all of these countries use Modern Standard Arabic for printed media. Its function however is different from that of Western standard languages: it is used for practically all writing, but is spoken only on formal or academic occasions. Consequently, prestigious vernacular varieties (especially Egyptian Arabic) fulfill some of the functions that standard languages have in Western countries (see Chambers, Sociolinguistic Theory).
"Colloquial Arabic" is a collective term for the spoken languages or dialects of people throughout the Arab world, which, as mentioned, differ radically from the literary language. The main dialectal division is between the Maghreb dialects and those of the Middle East, followed by that between sedentary dialects and the much more conservative Bedouin dialects. Maltese, though descended from Arabic, is considered a separate language. Speakers of some of these dialects are unable to converse with speakers of another dialect of Arabic; in particular, while Middle Easterners can generally understand one another, they often have trouble understanding North Africans (although the converse is not true, due to the popularity of Middle Eastern films and other media).
One factor in the differentiation of the dialects is influence from the languages previously spoken in the areas, which have typically provided a significant number of new words, and have sometimes also influenced pronunciation or word order; however, a much more significant factor for most dialects is, as among Romance languages, retention (or change of meaning) of different classical forms. Thus Iraqi aku, Levantine fiih, and North African kayen all mean "there is", and all come from Arabic (yakuun, fiihi, kaa'in respectively), but now sound very different.
The main groups are:
The Arabic alphabet derives from the Aramaic script (which variety, Nabataean or Syriac, is a matter of scholarly dispute), to which it bears a loose resemblance like that of Coptic or Cyrillic script to Greek script. Traditionally, there were several differences between the Western (Maghrebi) and Eastern version of the alphabet - in particular, the fa and qaf had a dot underneath and a single dot above respectively in the Maghreb, and the order of the letters was slightly different (at least when they were used as numerals.) However, the old Maghrebi variant has been abandoned except for calligraphic purposes in the Maghreb itself, and remains in use mainly in the Quranic schools (zaouias) of West Africa. Arabic, like Hebrew, is written from right to left. (note the "â" is inbetween "a" (car) and "e" (bed).