Mardi Gras is on February 13, 2018. The terms "Mardi Gras", "Mardi Gras season", and "Carnival season", in English, refer to events of the Carnival celebrations, beginning on or after Epiphany and ending on the day before Ash Wednesday. Mardi Gras is French for "Fat Tuesday", referring to the practice of the last night of eating richer, fatty foods before the ritual fasting of the Lenten season, which started on Ash Wednesday.
Related popular practices were associated with celebrations before the fasting and religious obligations associated with the penitential season of Lent. Popular practices included wearing masks and costumes, overturning social conventions, dancing, sports competitions, parades, etc. Similar expressions to Mardi Gras appear in other European languages sharing the Christian tradition. In English, the day is called Shrove Tuesday, associated with the religious requirement for confession before Lent begins.
Carnival is an important celebration in Catholic European nations. In the United Kingdom and Ireland, the week before Ash Wednesday is called "shrovetide", ending on Shrove Tuesday. It has its popular celebratory aspects as well. Pancakes are a traditional food. Pancakes and related fried breads or pastries made with sugar, fat and eggs are also traditionally consumed at this time in many parts of Latin America and the Caribbean. (With material from Wikipedia)