As we all know, yesterday was Mardi Gras (Fat Tuesday/Shrove Tuesday), and today is Ash Wednesday. It's one of the holiest days in the Catholic tradition...but what does it really signify, or mean, for Catholics, and Latinos?

Well, of course, according to About.com, Ash Wednesday kicks off the Lenten season, which marks the 40 days before Easter (Sundays, according to the Catholic tradition, are not included in the count). Traditionally, the forty days are symbolic of the time Jesus spent in the desert, avoiding temptation by Satan.

During this time, the faithful observe a period of "fasting, penance, moderation, and spiritual discipline." In many traditions, the priest rubs a cross of ashes on the forehead of the faithful.

It's not only Catholics that subscribe to the beliefs of Ash Wednesday: many Protestant denominations, including Lutherans, Methodists, Presbyterians, and Anglicans, put the practice into play.

Sister Joan Chittister spoke to The Huffington Post about the importance of Ash Wednesday for all, including Latinos: the opportunity to begin again. "Lent is a call to weep for what we could have been and are not. Lent is the grace to grieve for what we should have done and did not. Lent is the opportunity to change what we ought to change but have not. Lent is not about penance. Lent is about becoming, doing and changing whatever it is that is blocking the fullness of life in us right now. Lent is a summons to live anew," she writes.

During Lent, of course, many people give up something -- usually treats that they like to eat -- or they make a resolution to do better things (stay faithful to their wife, be a better girlfriend, etc.). Ash Wednesday derives its name from the practice of placing ashes (formally called The Imposition of Ashes)on the foreheads of adherents as a celebration and reminder of human mortality, and as a sign of mourning and repentance to God. The ashes used are typically gathered from the burning of the palms from the previous year's Palm Sunday.