Algorithms and much of the theory of trigonometry came from the Muslim world.
Algebra was named after al-Khwarizmi's book, Al-Jabr wa-al-Muqabilah, much of whose contents are still in use!
The work of Muslim maths scholars was imported into Europe 300 years later by the Italian mathematician Fibonacci.
And Al-Kindi's discovery of frequency analysis rendered all the codes of the ancient world soluble and created the basis of modern cryptology.
The modern cheque comes from the Arabic saqq, a written vow to pay for goods when they were delivered, to avoid money having to be transported across dangerous terrain.
In the 9th century, a Muslim businessman could cash a cheque in China drawn on his bank in Baghdad.
