Qadr in Islam refers to destiny or the divine decree of Allah (God) regarding all that occurs in the universe. It is the belief that everything, including all events and actions of human beings, has been predetermined by Allah and is written in a divine decree known as al-Lauh al-Mahfuz, the Preserved Tablet.
In a simple and comprehensive way, Qadr can be understood as the concept that Allah has complete control over all things and that everything that happens in the world, whether good or bad, is part of His plan. This belief is an important aspect of Islamic theology and helps Muslims to trust in Allah's wisdom and mercy, even in difficult circumstances.