The Compendious Book on Calculation by Completion and Balancing
The Compendious Book on Calculation by Completion and Balancing (, al-Kitāb al-Mukhtaṣar fī Ḥisāb al-Jabr wal-Muqābalah; ), also known as Al-Jabr (), is a mathematical book on algebra written by  Muḥammad ibn Mūsā al-Khwārizmī around 820 CE. Al-Jabr was important in the history of mathematics, the term "algebra" itself derived from Al-Jabr.