The only thing that you absolutely have to know, is the location of the library – Albert Einstein.
This separate elongated building is one of those structures usually called “libraries” in descriptions of Khmer art. Normally, they are placed south-east of the temple proper and large temples have many libraries. Their purpose is unclear, but the term library may be appropriate: modern monastery compounds in Southeast Asia have a separate building within the temple courtyard for safekeeping of Holy Scriptures or liturgical divices. Beng Mealea has two library buildings in the courtyards between exterior (third) and second enclosing galleries.