Saum (Fast) is a third Pillar of Islam. Allah's Messenger said, Allah says: "Every deed of the son of Adam is for him, except Saum (fasting). It is for Me and I shall reward for it." As the status of this act of worship is so high it is essential to learn the pilings pertaining to this month of fasting so that Muslims will know what is obligatory in order to do it, what is forbidden to avoid it, and what is permissible so that they do not unnecessarily subject themselves to any hardship by depriving themselves from it. This book consists of all the main issues of Fast. The main objective of this work is to serve an easy and authentic reference to the reader.