Dictionary.com defines a sacrament as a visible sign of an inward grace, especially one of the solemn Christian rites considered to have been instituted by Jesus Christ to symbolize ( Most Protestant Churches ) or confer grace ( Catholic ). With a sacrament, something is said and an action is taken.
Baptism and The Lord's Supper ( Holy Communion - The Eucharist ) are the two primary sacraments of most Protestant churches that are commonly seen as symbolic. However, the Church of Christ views Baptism as necessary for salvation and the Lutherans believe in consubstantiation ( The doctrine, especially in Lutheran belief, that the substance of the bread and wine coexists with the body and blood of Christ in the Eucharist. ) in Holy Communion.
CCC below is The Catechism of the Catholic Church and the associated number to find the text.
The Sacraments of Initiation:
Baptism (CCC 1226):
From the very day of Pentecost the Church has celebrated and administered holy Baptism. Indeed St. Peter declares to the crowd astounded by his preaching: "Repent, and be baptized every one of you in the name of Jesus Christ for the forgiveness of your sins; and you shall receive the gift of the Holy Spirit." The apostles and their collaborators offer Baptism to anyone who believed in Jesus: Jews, the God-fearing, pagans. Always, Baptism is seen as connected with faith: "Believe in the Lord Jesus, and you will be saved, you and your household," St. Paul declared to his jailer in Philippi. And the narrative continues, the jailer "was baptized at once, with all his family."
Additional Information: The Catholic Church recognizes Baptism that is done "In the name of the Father, and of the Son and of the Holy Spirit," so someone does not have to be re-baptized when becoming a Catholic provided the Baptism is considered valid. The Catholic Church also baptizes infants. Although Baptism is often done by pouring water three times ( "In the name of the Father, and of the Son and of the Holy Spirit" ) the Catholic Church has no issue with Baptism by immersion. The Catholic Church also teaches that there are three types of Baptism: Water ( the ordinary way ), Desire and Blood.
Confirmation (CCC 1288):
From [Pentecost] on the apostles, in fulfillment of Christ's will, imparted to the newly baptized by the laying on of hands the gift of the Spirit that completes the grace of Baptism. For this reason in the Letter to the Hebrews the doctrine concerning Baptism and the laying on of hands is listed among the first elements of Christian instruction. The imposition of hands is rightly recognized by the Catholic tradition as the origin of the sacrament of Confirmation, which in a certain way perpetuates the grace of Pentecost in the Church.
Additional Information: Confirmation goes far deeper than shaking the preachers hand to be a member of the church and is key to becoming a Catholic. A Christian enters the Catholic Church with a profession of faith, "I believe and profess all that the holy Catholic Church believes, teaches, and proclaims to be revealed by God" and a formal reception held during the Easter Vigil ( there are exceptions ) that includes Confirmation and The Eucharist. Take a look at this PDF from USCCB.org for more on Confirmation.
Eucharist (CCC 1323):
At the Last Supper, on the night he was betrayed, our Savior instituted the Eucharistic sacrifice of his Body and Blood. This he did in order to perpetuate the sacrifice of the cross throughout the ages until he should come again, and so to entrust to his beloved Spouse, the Church, a memorial of his death and resurrection: a sacrament of love, a sign of unity, a bond of charity, a Paschal banquet “in which Christ is consumed, the mind is filled with grace, and a pledge of future glory is given to us.”
Additional Information: The Eucharist ( Holy Communion ) is the pinnacle of every Catholic Mass. The Catholic Church teaches "the real presence" which is known as transubstantiation. Check out one of many resources to learn more about The Eucharist which is not merely symbolic and only done once per quarter.
The Sacraments of Healing:
Penance ( CCC 1446):
Christ instituted the sacrament of Penance for all sinful members of his Church: above all for those who, since Baptism, have fallen into grave sin, and have thus lost their baptismal grace and wounded ecclesial communion. It is to them that the sacrament of Penance offers a new possibility to convert and to recover the grace of justification. The Fathers of the Church present this sacrament as "the second plank [of salvation] after the shipwreck which is the loss of grace."
Additional Information: Penance is also known as Confession. Catholics confess to a priest but also offer an act of contrition to God while in the confessional. Here's an example of an act of contrition prayer: "O my God, I am sorry for my sins because I have offended you. I know I should love you above all things. Help me to do penance, to do better, and to avoid anything that might lead me to sin. Amen." As of this writing, I am still on my Catholic journey and have not been to confession. However, just thinking about confessing to a priest has made me more conscience of my sin and knowing that I can hear the priest give me absolution is something that I find refreshing.
Anointing of the Sick (CCC 1510):
However, the apostolic Church has its own rite for the sick, attested to by St. James: "Is any among you sick? Let him call for the elders [presbyters] of the Church and let them pray over him, anointing him with oil in the name of the Lord; and the prayer of faith will save the sick man, and the Lord will raise him up; and if he has committed sins, he will be forgiven." Tradition has recognized in this rite one of the seven sacraments.
The Sacraments of Service:
Holy Orders (CCC 1555):
Amongst those various offices which have been exercised in the Church from the earliest times the chief place, according to the witness of tradition, is held by the function of those who, through their appointment to the dignity and responsibility of bishop, and in virtue consequently of the unbroken succession going back to the beginning, are regarded as transmitters of the apostolic line.
Matrimony (CCC 1601):
The matrimonial covenant, by which a man and a woman establish between themselves a partnership of the whole of life, is by its nature ordered toward the good of the spouses and the procreation and education of offspring; this covenant between baptized persons has been raised by Christ the Lord to the dignity of a sacrament.