Why do we celebrate?
It is a way for people to remember the dead, the many lessons they've shared, the history of a family, and to celebrate the fulfilling lives they led. It also gives those a way to celebrate their connection to their religion as the Day of the Dead is celebrated as All Souls Day and All Saints Day for the Catholic Church. Día de los Muertos is celebrated not just across Mexico, but also in U.S. cities such as Los Angeles and New York, where large offerings, parades, and cultural events are held. Countries like Spain, the Philippines, Brazil, and Guatemala, among others, also have traditions to celebrate their deceased. Both public places and homes are filled with altars or offerings to commemorate loved ones with their favorite things, and decorations include cempasúchil flowers (marigolds), paper cut-outs, candles, salt, water, chocolate, sugar skulls, pan de muerto (bread of the dead) and the favorite foods and liquor of the deceased. --NBC News