Kurds, who are also known as Kurdish people, usually bilingual people who speak their national languages along with Kurdish language which is generally known by all Kurds irrespective of the area in which they are living. They are also aware of Turkish, Persian and Arabic according to their living areas.
On the other hand, the Arabs usually speak only Arabic which is a semantic language and it is a very ancient language that has been used in Arabia for many centuries and still there are a huge population that speaks this language not only in Arabia but also in different countries of the world.
The Kurdish Jews and Kurdish Christians are also expert in three or four languages. Along with Kurdish and their local languages, they are also fluent in Aramaic.
On the contrary, the Arabs are not master of three or four languages because in major Arab countries the main or official language is Arabic and a huge majority of Arabs only speaks Arabic.
Kurds are the native inhabitants of Middle East. However, there are many other countries where Kurds have a clear majority and among these countries Turkey, Iraq, Syria and Iran are the most notable ones.
While Arabs are the natives of Saudi Arabia and they also have a huge population in the countries of North Africa and West Asia.
Religiously, Kurds are usually Sunni Muslims but there are also different minorities in Kurds including Shia Muslims, Kurdish Jews and Kurdish Christians.
On the other hand, Arabs are comprised on Sunni Muslims, Shia Muslims, and Ismaili Muslims. However, there are also minorities like Arab Christians and Jewish Arabs.