Lenten Observances of Fast and Abstinence
"The seasons and days of penance in the course of the liturgical year (Lent, and each Friday in memory of the death of the Lord) are intense moments of the Church's penitential practice. These times are particularly appropriate for spiritual exercises, penitential liturgies, pilgrimages as signs of penance, voluntary self-denial such as fasting and almsgiving, and fraternal sharing (charitable and missionary works)." - CCC 1438
Ash Wednesday, March 1, and Good Friday, April 14, are days of fast and abstinence (from meat) in the universal Church. All Fridays of Lent are days of abstinence (from meat) in the Church in the United States.
Fasting - The Law of Fasting binds all Catholics age 18 and over until the beginning of their 60th year. Fasting means having only one full meal on that day. Two smaller meals may be eaten if necessary to maintain strength, however, those meals should not equal another full meal.
Abstinence - The Law of Abstinence binds all Catholics aged 14 and older.