If Eastertide is the “Sunday” of the Church year, then the year must also have a “Friday.”  Just as one cannot get to Sunday (the day of resurrection) without passing through Friday and Saturday (the days of passion, death, and entombment), so also one cannot get to the season of Eastertide without passing through a season of fasting and preparation.  Lent is just such a season. 
Initially, the word “Lent” simply meant “Spring” and derives from the Germanic root for “long” because, in Spring, the days visibly lengthen.
That Lent is a season consisting of forty days is rather well known.  But, if one were to look at a calendar and begin counting from Ash Wednesday to the Saturday before Easter, the result would not be forty days but forty-six days!  The reason for this is that the forty days of Lent are days of fasting. But, as previously mentioned, the Lord’s Day is always a feast day for the church.  So, in order to have forty days of fasting, the six Sundays of Lent must be excluded from the count.  Lent, in truth, is forty weekdays plus six Lord’s Days.
But, why forty days?  The number of days for Lent was inspired by the forty days during which Jesus endured temptation in the wilderness.  This was a time of Jesus’ own preparation for his public ministry—a time marked by his fasting those forty days in the desert.
The liturgical color for the season of Lent is purple.  Purple represents penitence because it signifies the feeling of sorrow for our sins in the light of Christ's passion and death.  Purple symbolizes suffering, and therefore, mourning and penitence.  It is indeed proper and fitting for us to mark the season of Lent with the holy color of purple.