He was born and educated in Kufa, before going to pursue further studies in Baghdad. Al-Kindi became a prominent figure in the House of Wisdom (a library and translation institute in Abbassid-era Baghdad. It is considered to have been a major intellectual center of the Islamic Golden Age), and a number of Abbasid Caliphs appointed him to oversee the translation of Greek scientific and philosophical texts into the Arabic language. This contact with "the philosophy of the ancients" (as Greek philosophy was often referred to by Muslim scholars) had a profound effect on his intellectual development, and lead him to write a number of original treatises of his own on a range of subjects ranging from metaphysics and ethics to mathematics and pharmacology.
The central theme underpinning al-Kindi's philosophical writings is the compatibility between philosophy and other "orthodox" Islamic sciences, particularly theology. And many of his works deal with subjects that theology had an immediate interest in. These include the nature of God, the soul and prophetic knowledge. But despite the important role he played in making philosophy accessible to Muslim intellectuals, his own philosophical output was largely overshadowed by that of al-Farabi and very few of his texts are available for modern scholars to examine. Despite this, he is still considered to be one of the greatest philosophers of Arab descent, and for this reason is known simply as "The Arab Philosopher".
In the field of mathematics, al-Kindi played an important role in introducing Indian numerals to the Islamic and Christian world. He was a pioneer in cryptanalysis and devised several new methods of breaking ciphers. Using his mathematical and medical expertise, he was able to develop a scale that would allow doctors to quantify the potency of their medication. He also experimented with music therapy.
And this is where it gets interesting: Al-Kindi was the first great theoretician of music in the Arab-Islamic World. He proposed adding a fifth string to the 'ud and discussed the cosmological connotations of music. He surpassed the achievement of the Greek musicians in using the alphabetical annotation for one-eighth of a beat. Al-Kindi realized also the therapeutic value of music and tried to cure a quadriplegic boy with musical therapy. He published fifteen treatises on music theory, but only five of those treatises have survived today. In one of his treaties the word musiqia was used for the first time in Arabic, which today means music in Arabic, Persian, Turkish, and several other languages in the world - and is the origin of that word we now know as "music".
I now feel validated with my music entries. Blessed indeed is the benefit of knowledge. Alhamdulillah.