This is true. Mardi Gras is French for Fat Tuesday. Some time ago, the tradition was to slaughter a fatted calf on the Tuesday before the beginning of the Lenten 40 day fast. T here is a distinction, however, between Mardi Gras and Carnival. Mardi Gras is a single day that is the climax for the Carnival season.
Carnival can run as long as two months, depending on the church calendar.
M ardi Gras day or Fat Tuesday is the traditional day for masking. However, you'll find people enjoying this tradition beginning the Friday before Mardi Gras day. Mardi Gras costumes are elaborate. Sequins and feathers rule the day. Families and friends often mask as a group.