Arabic is a Central Semitic language, thus related to and classified alongside other Semitic languages such as Hebrew and the Neo-Aramaic languages. In terms of speakers, Arabic is the largest member of the Semitic language family. It is spoken by more than 280 million people as a first language, most of whom live in the Middle East and North Africa, and by 250 million more as a second language. Arabic has many different, geographically-distributed spoken varieties, some of which are mutually unintelligible. Standard Arabic is widely taught in schools, universities, and used in workplaces, government and the media.Arabic has lent many words to other languages of the Islamic world. During the Middle Ages, Arabic was a major vehicle of culture in Europe, especially in science, mathematics and philosophy. As a result, many European languages have also borrowed many words from it. Arabic influence is seen in Mediterranean languages, particularly Spanish, Portuguese, and Sicilian, due to both the proximity of European and Arab civilization and 700 years of Arab rule in the Iberian peninsula .

Modern Standard Arabic derives from Classical Arabic, the only surviving member of the Old North Arabian dialect group, attested in Pre-Islamic Arabic inscriptions dating back to the 4th century.Classical Arabic has also been a literary language and the liturgical language of Islam since its inception in the 7th century.Arabic has also borrowed words from many languages, including Hebrew, Persian and Syriac in early centuries, and contemporary European languages in modern times.

Classical Arabic is the language found in the Qur'an and used from the period of Pre-Islamic Arabia to that of the Abbasid Caliphate. Classical Arabic is considered normative; modern authors attempt to follow the syntactic and grammatical norms laid down by classical grammarians (such as Sibawayh), and use the vocabulary defined in classical dictionaries .

Based on Classical Arabic, Modern Standard Arabic (fus'ha) is the literary language used in most current, printed Arabic publications, spoken by the Arabic media across North Africa and the Middle East, and understood by most educated Arabic speakers. "Literary Arabic" and "Standard Arabic" are less strictly defined terms that may refer to Modern Standard Arabic and/or Classical Arabic.

Colloquial or dialectal Arabic refers to the many national or regional varieties which constitute the everyday spoken language. Colloquial Arabic has many different regional variants; these sometimes differ enough to be mutually unintelligible and some linguists consider them distinct languages. The varieties are typically unwritten. They are often used in informal spoken media, such as soap operas and talk shows, as well as occasionally in certain forms of written media, such as poetry and printed advertising. The only variety of modern Arabic, through its descent from Siculo-Arabic, to have acquired official language status is Maltese, spoken in (predominately Roman Catholic) Malta and written with the Latin alphabet.

The sociolinguistic situation of Arabic in modern times provides a prime example of the linguistic phenomenon of diglossia, which is the normal use of two separate varieties of the same language, usually in different social situations. In the case of Arabic, educated Arabs of any nationality can be assumed to speak both their local dialect and their school-taught Standard Arabic. When educated Arabs of different dialects engage in conversation , many speakers code-switch back and forth between the dialectal and standard varieties of the language, sometimes even within the same sentence. Arabic speakers often improve their familiarity with other dialects via music or film.

Like other languages, Modern Standard Arabic continues to evolve. Many modern terms have entered into common usage; in some cases taken from other languages ilm) or coined from existing lexical resources . Structural influence from foreign languages or from the colloquial varieties has also affected Modern Standard Arabic. The influence of Arabic has been most important in Islamic countries. Arabic is a major source of vocabulary for languages such as Spanish, Sindhi, Punjabi, Gujarati, Portuguese, Berber, Kurdish, Pashto, Persian,Swahili, Urdu, Hindustani (especially the spoken variety), Turkish, Cypriot Greek, Malay, Rohingya, Bengali, Tagalog, and Indonesian, as well as other languages in countries where these languages are spoken. For example, the Arabic word for book has been borrowed in all the languages listed, with the exception of Spanish and Portuguese which use the Latin-derived words "libro" and "livro", respectively, and Tagalog which uses "aklat". In addition, English has quite a few Arabic loan words, some directly but most through the medium of other Mediterranean languages. Other languages such as Maltese[9] and Kinubi derive from Arabic, rather than merely borrowing vocabulary or grammar rules. Arabic words also made their way into several West African languages as Islam spread across the Sahara. Variants of Arabic words such as kitaab (book) have spread to the languages of African groups who had no direct contact with Arab traders.Arabic was influenced by other languages as well. The most important sources of borrowings into (pre-Islamic) Arabic are Aramaic, which used to be the principal, international language of communication throughout the ancient Near and Middle East, Ethiopic, and to a lesser degree Hebrew .