A "Feast Day" is a special day set aside in the Christian calendar to celebrate a particular saint, event, or aspect of faith. These days often involve religious ceremonies, prayers, and sometimes festive meals. Each feast day commemorates a specific occasion, such as the birth or death of a saint, and is observed by various Christian denominations, including Catholicism and Orthodoxy. Feast days can vary in significance and observance across different cultures and regions. Some are considered holy days of obligation, where attending mass is required, while others may be celebrated with local traditions and customs. Notable examples include the Feast of the Assumption and the Feast of All Saints.