Wikipedia states that:
Ash Wednesday is the first day of Lent and occurs forty days before Easter (excluding Sundays). It falls on a different date each year, because it is dependent on the date of Easter; it can occur as early as February 4 or as late as March 10. On this day Christians abstain from eating any kind of meat.
At Masses and services of worship on this day, ashes are imposed on the foreheads (or tonsure spots, in the case of some clergy) of the faithful. The priest, minister, or in some cases officiating layperson marks the forehead of each participant with black ashes in the shape of a cross, which the worshiper traditionally retains until washing it off after sundown. The act echoes the ancient Near Eastern tradition of throwing ash over one's head to signify repentance before God (as related in the Bible).
Today's workday was started with a mass which gave all of us a chance to take part in this catholic ritual. I'm hoping it would bring about true penance for us all to bring about the real meaning of the lenten season.