The 32 page Understanding Zakah book will help you better understand the history and philosophy of Zakah. It has a calculation guide as well, thereby making is a more comprehensive read for first-time or frequent payers of Zakah.
Zakáh is one of the five fundamental institutions of Islam. It is second only to prayer as an essential article of the faith. Zakáh forms an integral, compulsory and inseparable part of the Islamic way of life. The non-observance or neglect of Zakáh is tantamount to a negation of the faith itself. The early Meccan revelations emphasized the moral aspect of Zakáh and persuaded Muslims to offer it voluntarily. It was not until the second year of Hijrah that Zakáh was made obligatory on all Muslims.