Ash Wednesday marks the first day of the 40-day Lenten fast for Western Christians. The Christian holy day, this year falling on Feb. 18, is observed by prayer, repentance and fasting ahead of Easter.

The day follows Fat Tuesday, also known as Mardi Gras, where revelers partake in their last bout of merrymaking before Lent begins. While many see the observance as a Catholic one, most liturgical churches include Lent in their practices. This includes Lutheran, Methodist, Presbyterian and Anglican denominations.

For those unfamiliar with Ash Wednesday, below are three answers to common questions surrounding the holy day.

How Is Ash Wednesday Observed?

During Ash Wednesday services, clergy use ashes burned at last year’s Palm Sunday to mark a cross on member’s foreheads as they bow. While services may take place in the morning and evening, churches have found innovative ways for members partake in the ritual. Some organizations dispense ashes on street corners, subway platforms, outside coffee shops and grocery stories. This year a number of churches are offering drive-through services where members can receive the ashes on their forehead from their car.   

For devout Catholics between the ages of 18 to 59, Ash Wednesday and Good Friday are mandatory fasting days. Abstinence -- in this case, refraining from meat products -- must be practiced from age 14 and up. Fasting denotes eating one full meal and two small meals each day. Lent is also a time to refrain from any bad habits that can interfere with one’s relationship with God. This can range from giving up chocolate to performing community outreach.

What Do The Ashes Mean?

Ash Wednesday and the 40-day Lenten fast are not mentioned in the Bible. Rather, Lent formally appeared in A.D. 325 after the Council of Nicaea.

Ash Wednesday comes from the Latin name "dies cinerum" (day of ashes). The earliest record of the practice comes from copies of the Gregorian Sacramentary around the eighth century when the faithful would approach the altar and a priest would mark their heads with the sign of the cross in ashes.

Even before their liturgical use, ashes were seen as a sign of repentance. The Hebrew Bible makes several references to how ashes symbolized mourning, mortality and penance. Biblical figures including Jonah, Job and Daniel usesd sackcloths and ashes to repent. Until the Middle Ages, ashes adopted a symbolic meaning. Around the eighth century, the church began sprinkling ashes on those who were about to die, referencing the biblical passage in Genesis 3:19: “For dust you are and to dust you shall return.”

Over time, ashes were used to mark the beginning of Lent. An early reference to sign one’s forehead with the shape of the cross was written in the year A.D. 1000 by an Anglo-Saxon abbot named Ælfric of Eynsham who remarked, “We read in the books both in the Old Law and in the New that the men who repented of their sins bestrewed themselves with ashes and clothed their bodies with sackcloth. Now let us do this little at the beginning of our Lent that we strew ashes upon our heads to signify that we ought to repent of our sins during the Lenten fast."

What Is Clean Monday?

Ash Wednesday is a Western Christian tradition. For those belonging to Eastern Orthodox churches, Lent starts on a Monday.

Eastern Catholics (e.g., Coptic Christians, etc.) start the Lenten fast on the Monday preceding Ash Wednesday. Eastern Orthodox churches begin Lent later, on the Monday after Ash Wednesday. Known as Clean Monday, the date falls seven weeks before Easter. This year Clean Monday falls on Feb. 23.

Unlike Western traditions that exclude Sundays in their 40-day counts, Orthodox traditions include them as fasting days. The idea of starting the fast on Monday, the first day of the week, acts as a reminder to start the Lenten season with the intention of spiritually purifying oneself. Orthodox Christians follow stricter fasting rules during this time where they refrain from meat, eggs and dairy products.