Halloween is a celebration on the night of October 31. It is most practiced in the United States, Australia and Canada. Children wear costumes and go to people's homes saying "Trick or treat!" to ask for candy (sweets in the UK) and people give it to them. People traditionally dress up as ghosts, witches, or other scary things for Halloween.[1]
For Christians it is the eve of All Saints' Day, which begins the three-day observance of Allhallowtide. This covers the three days – October 31 (All-Hallows Eve or Halloween), November 1 (All Saints) and November 2 (All Souls). All Hallows' is a Christianized holiday and originated in Ireland. It also has pagan roots.[2][3]