Halloween is a day people all over the world celebrate. It is now celebrated by dressing up in costume and walking around the neighbourhood saying trick or treat, hoping for a reply of lollies. The original way of celebrating Halloween was by wearing costumes and walking around a bonfire. This was meant to ward off ghosts and spirits.
There are 2 ways of celebrating Halloween. It really depended what country you were in.
Romans and druids believed that the god, Samhain, summoned wicked witches and souls and condemned them into animals. People though that the animals, would harm then so they sacrificed something to the god, so they would not be harmed. They day of the sacrifice was October 31st.
The second way of celebrating was in England and spread throughout America and Austria. Halloween first started in the eighth century. Pope Gregory III, designated November the 1st for the day to acknowledge all saints and martyrs. It was called all saints day.
Through out the years, English changed and the name All Saints Day was converted to All Hallows Eve and later on, changed to Halloween. The date was also moved to October 31st.