It is almost a consensus among scholars that, in the 3rd century of Hijra, a huge number of Muslim scholars and Mohadithin were driven by a common sense of religious and social responsibility to collect and preserve the Hadiths of holy Messenger Mohammad (PBUH) in written shape. For this purpose, some scholars spent most times of their lives studying, investigating, traveling, interviewing, and searching the truth about Hadiths of Great Prophet (PBUH) and its narrators. They applied multiples techniques and methods to acquire their goal. The most famous scholars in this process were al-Imam al-Bukhari, (d. 194 AH to 256 AH) and al- Imam-Muslim (d.204 AH to 261 AH). Their books are known as Sahihain, genuine and systematic books in the field of hadith. This paper will discuss, investigate, and analyze Hadith compilation, its methodology in general, and Sahihain in particular. So in this research, there is a description circumstantially the compilation of Sahih al Bukhari and Sahih Muslim. There will be a detailed description circumstantially the compilation and competitive analytical study of (Sahihain) Sahih al Bukhari and Sahih Muslim.
Keywords: Sahih Bukhari, Sahih Muslim, Imam Muslim, Imam Bukhari, Hadith