The Latin word sacramentum means "a sign of the sacred." The seven sacraments are rituals that point to what is sacred, significant and important for Catholics. They are special occasions for experiencing God's saving Grace. That's what theologians mean when they say that sacraments are at the same time signs and instruments of God's grace.
Baptism Infants 0 to 6 years of age Children through Adults, 7 years and older