Grandparents are the parents of a person's own parent, whether that be a father or a mother. Every sexually-reproducing creature who is not a genetic chimera has a maximum of four genetic grandparents, eight genetic great-grandparents, sixteen genetic great-great-grandparents, etc. Rarely, such as in the case of sibling or half-sibling incest, these numbers are lower. In the history of modern humanity, around 30,000 years ago, the number of modern humans who lived to be grandparents began to skyrocket. It is not known for certain what spurred this increase in longevity. But it is believed that a key consequence of three generations being alive together was the facilitation of the passing along of information that prior to that point would have been lost; an example of this important information might have been where to find water in times of drought.
In cases where parents are unwilling or unable to provide adequate care for their children (e.g., death of the parents), grandparents often take on the role of primary caregivers. Even when this is not the case, and particularly in traditional cultures, grandparents often have a direct and clear role in relation to the raising, care and nurture of children.
One can also be a step-grandparent. A step-grandparent can be one's parent's step-parent or one's step-parent's parent or one's step-parent's step-parent. The various words for grandparents at times may also be used to refer to any elderly person, especially the terms gramps, granny, grandfather, grandmother and even more types that most families make up themselves.
When used as a noun (e.g., "... a grandparent walked by"), grandfather and grandmother are usually used, although grandpa/grandma and granddaddy/granny are often used. When preceded by "my ..." (i.e., "... my grandpa walked by"), all forms are common (anywhere from "... my grandfather ..." to "... my Gramps ..."). All forms can be used in plural, but Gramps (plural Gramps) is rare.
In writing, Grandfather and Grandmother are most common, but very rare when referring to a grandparent in person. In speech, Grandpa and Grandma are sometimes used in the United States and Canada. In Britain, Ireland, United States, Australia, New Zealand and Newfoundland and Labrador, Nan, Nana, Nanan, Nannan, Nanna, Nada, Nanny, Gran and Granny and other variations are often used for grandmother in both writing and speech.
In many parts of India maternal grandparents are called Nana and Nani. Similarly fathers side grandparents are called Dada and Dadi.
Numerous other variants exist, such as Gramp, Grandpap, Grampy, Granddad, Granddaddy, Grandpappy, Pop, and Pappy for grandfather; Grandmom, Grandmama, Granny; Gran, Nanny, Nan and Grammy for grandmother. Gogo can be used for either, etc.
Given that people may have two living sets of grandparents, some confusion arises from calling two people "grandma" or "grandpa", so often two of the other terms listed above are used for one set of grandparents. Another common solution is to call grandparents by their first names ("Grandpa George", "Grandma Anne", etc.) or by their family names ("Grandpa Jones", "Grandma Smith"). In North America, many families call one set of grandparents by their ethnic names (i.e., Hispanic grandparents might be called "Abuelo" and "Abuela", French grandparents might be called "Pépé" and "Mémé", Italian grandparents might be called "Nonno" and "Nonna", or Dutch and German grandparents might be called "Opa" and "Oma").
Languages and cultures with more specific kinship terminology than English may distinguish between paternal grandparents and maternal grandparents. For example in the Swedish language there is no single word for "grandmother"; the mother's mother is termed mormor and the father's mother is termed farmor. Where the other Scandinavian languages, Danish and Norwegian, use words which specifies the kinship like in Swedish (identically spelled among all three languages). As well as using common terms similar to grandmother (Danish: bedstemor, Norwegian: bestemor).
The parents of a grandparent, or the grandparents of a parent are called all the same names (grandfather/-mother, grandpa/-ma, granddad/-ma, etc.) with the prefix great- added, one for each additional generation. One's great-grandparent's parents would be "great-great-grandparents". To avoid a proliferation of "greats" when discussing genealogical trees, one may also use ordinals instead of multiple "greats"; thus a "great-great-grandfather" would be the "second great-grandfather", and a "great-great-great-grandfather" would be a third great-grandfather, and so on. This system is used by some genealogical websites such as Geni. Individuals who share the same great-grandparents but are not siblings or first cousins are called "second Cousins" to each other, as second cousins are the grandchildren of one's grandparent's siblings.
History of the term 
The use of the prefix "grand-" dates from the early 13th century, from the Anglo-French graund. The term was used as a translation of Latin magnus. The prefix "great-" represents a direct translation of magnus to English. In Old English, the prefixes ealde- (old) and ieldra- (elder) were used (ealdefæder/-mōdor and ieldrafæder/-mōdor). A great-grandfather was called a þridda fæder (third father), a great-great-grandfather a fēowerða fæder (fourth father), etc.
Grandparents in non-Western culture 
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In traditional East Asian cultures influenced by Confucianism, filial piety is one of the highest moral values. Grandparents in non-Western cultures can hold more authority over the matters of a family such as child raising, attitudes and values. This kind of structure has eased with the increasing influence of Western culture and the increasing number of nuclear families.
See also 
- Middle age
- Midlife crisis
- Grandparent rule
- Grandfather clause
- Wong, Kate. "The Mysterious Downfall of the Neandertals". Scientific American. Retrieved 2013-03-24.
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- Dale, Philip S.; Ingram, David, eds. (1981), Child language, an international perspective: selected papers from the First International Congress for the Study of Child Language 1, Baltimore, Maryland: University Park Press, p. 275, ISBN 978-0-8391-1608-0, OCLC 6863252
- "Family Tree & Family History at". Geni.com. Retrieved 2013-03-24.
- "Online Etymology Dictionary". Etymonline.com. Retrieved 2013-03-24.
- "Online Etymology Dictionary". Etymonline.com. 1957-10-01. Retrieved 2013-03-24.
|Look up grandparent, grandfather, grandmother, grandpa, or grandma in Wiktionary, the free dictionary.|
|Wikimedia Commons has media related to: Grandparents|
- Grandparenting support database AARP
- Links to Australian grandparent support groups
- Family therapy for grandparents raising grandchildren in crisis