Unmarked grave

In many cultures graves are marked with durable markers, or monuments, intended to help remind people of the buried person. An Unmarked Grave is a grave with no such memorial marker.

The phrase "unmarked grave" has metaphorical meaning in the context of cultures that mark burial sites. As a figure of speech, an unmarked grave represents consignment to oblivion, an ignominious end. As a monument is a sign of fondness or respect, similarly a grave with no marker is a sign of disdain and disrespect - representing an intent that the person be forgotten utterly.

The corpus of Pope Formosus was actually disinterred, placed on trial, found guilty, and ultimately thrown into an 'unmarked grave' -- the waters of the River Tiber.

Anonymous burial

Another sort of unmarked grave is a burial site with an anonymous marker, such as a simple crucifix; boots, rifle and helmet; a sword and shield; a cairn of stones; or even lavish monuments. In this type of unmarked grave, no disrespect is intended. Rather, identification of the departed is impossible, yet it is desired that they be memorialized.

The United Kingdom has buried one of their unknown warriors in Westminster Abbey. France likewise honors an unknown soldier by burial underneath the Arc de Triomphe, Italy honors an unknown soldier in the Monumento al Milite Ignoto in Rome, and the Tomb of the Unknown Soldier, a monument in the U.S.'s Arlington National Cemetery is dedicated to American military personnel who have died without their remains being identified. These are extreme examples of anonymous graves, where the anonymity of the dead person is symbolic, indicating respect for all the unknown departed of war or calamity on a national scale.

Secret burial

In some very rare cases, a person will be buried without identification, even when their identity is known. In some cases of infamous or notorious figures, this is to avoid desecration of the corpse or vandalism of the site. In others it may be for exactly the opposite reason. Famous graves often become tourist attractions, or destinations of pilgrimage. To avoid this the family or friends honoring the dead might bury them in an unpublicized place, a secret location, or in a grave with a false name — or no name at all — on the marker.

Walt Disney was cremated and the ashes buried in a secret location — Forest Lawn Memorial Park Cemetery — one of many cemeteries that cater to the needs of famous dead people. Some burial sites at Forest Lawn, such as those of Humphrey Bogart and Mary Pickford, are secluded in private gated gardens, with no entry for the public. A number of tombs are also kept from the public eye. Forest Lawn's Court of Honour advertises that in some of the crypts beneath it are spots which no amount of money can buy, but individuals may be "voted in" as "Immortals." Out of respect for the privacy of the dead, no photographs taken at Forest Lawn are ever allowed to be published, and their information office usually refuses to say where famous people are buried.
 

Multiple bodies per grave

Some couples or groups of people want to be buried together, for example, a husband and wife. Since (in many cases) people die at different times, the exhumation of the first to die is often necessary. In other cases, the bodies may simply be buried side by side. Or if there were advanced planning the first person buried will be at a greater depth so that the second person can be buried on top at a shallower depth.

Mass burials

Mass burial is the practice of burying dozens, hundreds, or thousands of individuals in one massive pit, much like a landfill for human remains. Most cultures view mass burial as a way of objectifying corpses, and is often viewed as a form of gross disrespect to the individuals being buried. Civilizations attempting genocide often employ mass burial for the people they kill in the genocide, as it is mechanically efficient, and coincides neatly with their goals of dehumanizing and destroying a segment of the population.

However, in the case of mass disasters, or epidemics, mass burial is the only practical means of dealing with a number of corpses sufficient to overwhelm local resources.

In cases of mass burial, it is commonly of importance to survivors to later have the bodies exhumed, identified, and buried properly.

Animals burial

In addition to burying human remains, many human cultures also regularly bury animal remains. This is often necessary for hygienic reasons when the body cannot be disposed of in another way. 

Pets and other animals of emotional significance are often ceremonially buried. Most families bury deceased pets on their own properties, mainly in a yard, with a shoe box or any other type of container served as a coffin. The Ancient Egyptians are known to have mummified and buried cats, which they considered deities.

Live burial

Live burial sometimes occurs, in which individuals are buried while still alive. Having no way of escaping interment, they die in place, typically by asphyxiation, dehydration, starvation, or (in cold climates) exposure. People may come to be buried alive in a number of different ways:

• An individual may be intentionally buried alive as a method of execution or murder.
• In Ancient Egypt, servants were sometimes intentionally buried alive with their Pharaoh in order to serve him/her in the afterlife.
• A person or group of people in a cave, mine, or other underground area may be sealed underground due to an earthquake or other natural disaster.
  People have been unintentionally (uncommonly) buried alive because they were pronounced dead by a coroner or other official, when they were in fact still alive.