This book is a compilation of hadith from different periods. The whole period in which hadith were received is divided into 4 periods. Each one has a different explanation to justify hadith. Each period has different important aspects mentioned in it which contributed towards the compilation of hadith. These include things like famous memorizers, specificity of a certain period, important people who helped for compilation and some other important stuff. This is an important compilation for all those who want to get perfect and in depth knowledge of hadith.
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