On November 1,  the Church celebrates the heroic lives of all the saints in heaven, not only those who have been formally canonized. These “All Saints” or “All Hallows” are the reason the evening before is called “All Hallows Eve” or “Hallowe’en.”
This is a holy day of obligation for Catholics and Masses will be celebrated at noon and at 5:15pm in the Brothers' Chapel (St. Joseph Hall) on Friday.