Burial registers are lists of the people buried in a particular cemetery or burial place, generally created and maintained by whoever controlled the cemetery (e.g. parish priest, trustees, local council). Entries would normally be made at the time of burial or shortly after, so are usually in chronological order. The information in the register was either directly known to the person making the entry or provided by relatives, friends or neighbours. Thus the information is likely to be reasonably accurate (unless the deceased was a stranger or loner).
The information included in a burial register varies. At a minimum, there is usually a date and a name, although it may not uniquely identify the person such as "Mr Smith", "The widow Jones" or "infant Brown". Such a name may have been sufficient to identify the person at the time of burial but not when read many years later. Other burial register entries are more informative and may have full name, age, cause of death, residence, religion, and other interesting information.
Generally speaking, less information was recorded for older burials compared to more information for more recent burials. Records kept by governments and well-organized churches tend to be more complete than records kept by private trustees or small, less-organized churches. In some parts of the world, government regulations require certain information to be recorded and maintained.
Care should be taken with burial registers as some record the date of burial, others the date of death or both. Often you will find a date but with no clear indication as to whether it is the date of death or burial, so keep an open mind.
Burial registers can be a valuable resource when they are available. Usually written in paper ledgers, burial registers are often lost in fires and floods or damaged by vermin or other pests. Those responsible for the burial registers in older historical cemeteries may die and the records lost if control of the records is not passed to a responsible person.
Burial registers should not be confused with monumental inscriptions as not every burial has a surviving headstone to be recorded as a monumental inscription. Also burial registers are made at the time of burial, whereas monumental inscriptions are often recorded many years later.
As burial registers are usually in chronological order (ordered by date of death/burial), genealogists often create and consult alphabetical indexes.