The observance of Halloween (All Hallow's Eve) on October 31 has long been associated with images of witches, ghosts, devils and hobgoblins. The holiday dates back to the Celtic festival of Samhain thousands of years ago. The Celts believed that at the time of Samhain the ghosts of the dead were able to mingle with the living because that was when the souls of those who had died during the year traveled into the otherworld.
Over the years, Halloween customs and rituals have changed. Today, many Americans celebrate the traditions of Halloween by dressing in costumes and telling tales of witches and ghosts. Pumpkins are carved and children go from house to house, knocking on doors and calling out "trick or treat" hoping to have their bags filled with candy. Many communities also celebrate Halloween by holding local parties and parades.