Al-Khalīl ibn ’Ahmad al-Farāhīdī (الْخَلِيل بن أَحْمَد الْفَراهِيدِي), a grammarian who was born in 718 (100 AH) in present-day Oman. But that was not his only achievement…
The Arabic Collections Online are offering 10,000 Arabic ebooks across 6,000 subjects – for free. And it is legal.
A big one.
The early works on grammar as well as the first dictionaries were very much based on the spoken Arabic of Bedouins. The grammarians regarded the Bedouin as the true speaker of Arabic.
I recently was in Poznań, Poland, and learned by coincidence that one of the greatest Arab scholars, al-Kindī (الْكِنْدِي), was one of the pioneers of cryptology .