Ash Wednesday & all the Fridays of Lent are days of abstinence for Catholics. Ash Wednesday and Good Friday also are days of fasting. Here are the rules governing these obligations:
Abstinence: In the US, all who have reached their 14th birthday are obliged to abstain from meat on Ash Wednesday and all the Fridays of Lent.
Fasting: On the days of fast, only one full meal may be taken. Two other meals, sufficient to maintain strength, may be taken but together may not add up to a second full meal. Eating solid foods between meals is not permitted. The obligation to fast binds all between their 18th & 59th year.