I found this article from Catholic Online - Lent: that explains lent and some of the lenten practices beautifully. Here are some excerpts:
"Why is Baptism so important in our Lenten understanding? Lent as a 40-day season developed in the fourth century from three merging sources. The first was the ancient paschal fast that began as a two-day observance before Easter but was gradually lengthened to 40 days. The second was the catechumenate as a process of preparation for Baptism, including an intense period of preparation for the Sacraments of Initiation to be celebrated at Easter. The third was the Order of Penitents, which was modeled on the catechumenate and sought a second conversion for those who had fallen back into serious sin after Baptism. As the catechumens (candidates for Baptism) entered their final period of preparation for Baptism, the penitents and the rest of the community accompanied them on their journey and prepared to renew their baptismal vows at Easter."
Lent is about conversion, turning our lives more completely over to Christ and his way of life. That always involves giving up sin in some form. The goal is not just to abstain from sin for the duration of Lent but to root sin out of our lives forever. Conversion means leaving behind an old way of living and acting in order to embrace new life in Christ. For catechumens, Lent is a period intended to bring their initial conversion to completion.
The three traditional pillars of Lenten observance are prayer, fasting and almsgiving. The key to renewed appropriation
of these practices is to see their link to baptismal renewal.
Prayer: More time given to prayer during Lent should draw us closer to the Lord. We might pray especially for the grace to live out our baptismal promises more fully. We might pray for the elect who will be baptized at Easter and support their conversion journey by our prayer. We might pray for all those who will celebrate the sacrament of reconciliation with us during Lent that they will be truly renewed in their baptismal commitment.
Fasting: Fasting is one of the most ancient practices linked to Lent. In fact, the paschal fast predates Lent as we know it. The early Church fasted intensely for two days before the celebration of the Easter Vigil. This fast was later extended and became a 40-day period of fasting leading up to Easter. Vatican II called us to renew the observance of the ancient paschal fast: "...let the paschal fast be kept sacred. Let it be celebrated everywhere on Good Friday and, where possible, prolonged throughout Holy Saturday, so that the joys of the Sunday of the Resurrection may be attained with uplifted and clear mind" (Liturgy, # 110).
Fasting is more than a means of developing self-control. It is often an aid to prayer, as the pangs of hunger remind us of our hunger for God. The first reading on the Friday after Ash Wednesday points out another important dimension
of fasting. The prophet Isaiah insists that fasting without changing our behavior is not pleasing to God. "This, rather, is the fasting that I wish: releasing those bound unjustly, untying the thongs of the yoke; setting free the oppressed, breaking every yoke; sharing your bread with the hungry, sheltering the oppressed and the homeless; clothing the naked when you see them, and not turning your back on your own" (Is 58:6-7).
Fasting should be linked to our concern for those who are forced to fast by their poverty, those who suffer from the
injustices of our economic and political structures, those who
are in need for any reason. Thus fasting, too, is linked to living out our baptismal promises. By our Baptism, we are charged
with the responsibility of showing Christ's love to the world, especially to those in need. Fasting can help us realize the suffering that so many people in our world experience every day, and it should lead us to greater efforts to alleviate that suffering.
Abstaining from meat traditionally also linked us to the poor, who could seldom afford meat for their meals. It can do the same today if we remember the purpose of abstinence and embrace it as a spiritual link to those whose diets are sparse and simple. That should be the goal we set for ourselves—a sparse and simple meal. Avoiding meat while eating lobster misses the whole point!
Almsgiving: It should be obvious at this point that almsgiving, the third traditional pillar, is linked to our baptismal commitment in the same way. It is a sign of our care for those in need and an expression of our gratitude for all that God has given to us. Works of charity and the promotion of justice are integral elements of the Christian way of life we began when we were baptized.