Varieties of Arabic (or dialects or vernaculars) are the linguistic systems that Arabic speakers speak natively. Arabic is a Semitic language within the Afroasiatic family that originated in the Arabian Peninsula. There are considerable variations from region to region, with degrees of mutual intelligibility that are often related to geographical distance and some that are mutually unintelligible. Many aspects of the variability attested to in these modern variants can be found in the ancient Arabic dialects in the peninsula. Likewise, many of the features that characterize (or distinguish) the various modern variants can be attributed to the original settler dialects as well as local native languages and dialects. Some organizations, such as SIL International, consider these approximately 30 different varieties to be separate languages, while others, such as the Library of Congress, consider them all to be dialects of Arabic.
In terms of sociolinguistics, a major distinction exists between the formal standardized language, found mostly in writing or in prepared speech, and the widely diverging vernaculars, used for everyday speaking situations. The latter vary from country to country, from speaker to speaker (according to personal preferences, education and culture), and depending on the topic and situation. In other words, Arabic in its natural environment usually occurs in a situation of diglossia, which means that its native speakers often learn and use two linguistic forms substantially different from each other, the Modern Standard Arabic (MSA) as the official language and a local colloquial variety (called العامية, al-ʿāmmiyya in many Arab countries, meaning "slang" or "colloquial"; or called الدارجة, ad-dārija, meaning "common or everyday language" in the Maghreb), in different aspects of their lives.