This day, November 1, is a solemn day to celebrate and honor all saints, both known and unknown. The night before a feast day is a vigil in anticipation of the day, and is commonly referred to as the eve of the holiday. The Eve of All Saints Day is popularly known as Halloween and has come to be celebrated in much greater enthusiasm than is the feast day itself.
In America, and I won't attempt to speak for the rest of the world, Halloween has become a very big deal, celebrated by many as a favorite holiday. In popular culture it seems to have become so completely divorced from its origins that scarce there be a soul left who understands the religious significance of the day.
Happy Feast Day.