Dia de los Muertos (Day of the Dead) is a two-day festival that takes place every November 1 and 2. Although most strongly identified with Mexico, Dia de los Muertos is celebrated throughout Latin America and everywhere with a Latino population, including the US.
On Dia de los Muertos, the dead are awakened from their eternal slumber to become a vibrant part of the community. They are celebrated with objects and activities they enjoyed in life, such as food, drink, and music. Although the celebration is bittersweet and its symbols macabre, Dia de los Muertos honors the dead with festivals and lively celebrations, a typically Latin American custom that combines indigenous Aztec ritual with Catholicism, brought to the region by Spanish conquistadores.
Assured that the dead would be insulted by mourning or sadness, Dia de los Muertos celebrates the lives of the deceased with food, drink, parties, and activities the dead enjoyed in life. Dia de los Muertos recognizes death as a natural part of the human experience, a continuum with birth, childhood, and growing up to become a contributing member of the community. On Dia de los Muertos, the dead are also a part of the community, awakened from their eternal sleep to share celebrations with their loved ones.
The most familiar symbol of Dia de los Muertos may be the calacas and calaveras(skeletons and skulls), which appear everywhere during the holiday: in candied sweets, as parade masks, as dolls. Calacas and calaveras are almost always portrayed as enjoying life, often in fancy clothes and entertaining situations.
The following video is a nice visual explanation of Day of the Dead