Where did Arabic come from?
Arabic is in the Semitic language group. Semitic languages seem to have gotten started before the beginning of writing. That would be before about 3000 BC.
Probably Semitic languages developed from an earlier language somewhere near modern Syria. A different branch of that earlier language became Ancient Egyptian.
Semitic languages spread from Syria through Lebanon, Israel, and Jordan. Finally they reached the Arabian peninsula. Because the Arabian peninsula was more isolated, people there kept speaking this older version of the language.
But in Israel and Syria, Semitic languages mixed more with Indo-European and other language groups. So the language changed into Hebrew and Aramaic.
When did people start to write Arabic?
Until the time of Mohammed, in the 600s AD, people mostly spoke Arabic and didn’t write it. Still, there are some written records from the Arabian peninsula from before the 600s AD. We call these Sabataean. But Sabataean writing is only short inscriptions in stone, not literature.
Arabic and the alphabet
The alphabet first came to the Arabian peninsula not too much before 400 AD. Very soon, people used it to write Arabic. So the Arabic alphabet, like all the other alphabets in the world, comes from the first alphabet invented in the Levant (in the Sinai).
Arabic spreads to Africa and India
But Arabic had a bigger future ahead of it. After the Islamic conquests of the late 600s AD, people started to speak Arabic all over the Islamic Empire. People spoke Arabic from Afghanistan to Spain. By 1000 AD, some people knew Arabic even in India and East Africa.
Arabic religion and science
Arabic stories and histories
Arabic writers retold older stories from other places. The Greek story of Odysseus and the Cyclops finds its way into the story of Sinbad the Sailor. Arabic writers also retold the Buddhist Jataka Tales from India as Nasruddin stories. (You can compare stories about the trickster Nasruddin to African Anansi stories, too)
Islamic writing in Persian
But in the eastern part of the Islamic Empire, many people still spoke and wrote in Persian (an Indo-European language). One famous Persian story, written about 1000 AD, is the story of Sohrab and Rustem.
Here’s a song by Yusuf Islam (who used to be Cat Stevens) to teach the Arabic alphabet:
Islamic writing in Turkish
Beginning in the later medieval period, Turkic and Altaic people from Central Asia moved into West Asia. These people also told or wrote stories in Turkish. They wrote their own stories, like the Alpamysh.