Prayer is defined as the lifting up of our minds and hearts to God (CCC 2559). We do so in order to communicate with God. Simply put, prayer is conversation with God.
There are many types of prayer. These include blessing and adoration, praise, thanksgiving, petition, and intercession. Adoration is the acknowledgment of God as the Supreme, infinitely perfect, Being (CCC 2628). Praise is the acknowledgment of the greatness and power of God, where God is lauded for who He is (CCC 2639). Thanksgiving is the prayer by which we thank God for our blessings and for everything good that is attributable to God (CCC 2637). Petition is when we pray to God for any intention that we have (CCC 2633). Intercession is when we pray on behalf of others, for any intentions that they have (CCC 2635). "Petitions, prayers, and intercession" (1 Tim. 2:1) should be asked of other believers, whether they be in heaven or on earth (CCC 956).
There are three ways in which prayers are expressed–vocal, mental, and contemplative prayer. Vocal prayer is where we use our lips, or at least our words, to pray to God. However, this prayer should be heart-felt, and involve the mind, so that our vocal prayer is meaningful, and not just a set of empty words (CCC 2700): "This people honors me with their lips, but their hearts are far from me" (Mark 7:6). Mental prayer is where we pray with the mind, using our thoughts, and with meditations (CCC 2705). Our thoughts or meditations should excite the heart, through which we talk to God and listen to Him, with or without words. Contemplative prayer is a heavy preoccupation with God or His mysteries, so that it is constantly on the mind and absorbes the affections (CCC 2711, 2714).
Our prayers should have certain characteristics. We should pray with devotion, humility, resignation, confidence, and perseverence. Devotion is to pray with the heart, while avoiding distractions (which can be sinful if we allow our minds to wander rather than turning our attention back to God as soon as we become aware of these distractions) (CCC 2729). Humility is to admit our sinful state and our need for God's assistance in all things (CCC 2839): "The tax collector . . . would not even raise his eyes to heaven but beat his breast and prayed, ‘O God, be merciful to me a sinner'" (Luke 18:13). Resignation is to leave in God's hands how, when, and if he will answer our prayers (CCC 2737): ""My Father, if it is possible, let this cup pass from me; yet, not as I will, but as you will" (Matt. 26:39). Confidence is when we trust that God will hear us, and respond to our prayers the way He deems best, and grant what we ask Him if it is according to His will (CCC 2620): "Whatever you ask the Father in my name he will give you" (John 16:23; 1 John 5:14-15). Perseverence is to be persistent in prayer, even if our petitions have not yet been granted (CCC 2746): "Will not God then secure the rights of his chosen ones who call out to him day and night? Will he be slow to answer them?" (Luke 18:7).
Prayer is usually addressed to the Father (CCC 2664). For Christians, it is addressed to the Father in the name of Jesus because He is the "one mediator between God and man" (1 Tim. 2:5). We pray in the Holy Spirit, because "no one can say ‘Jesus is Lord' except by the Holy Spirit" (1 Cor. 12:3). It is the Holy Spirit that gives our prayer the strength, power, and grace that is necessary (CCC 2670).
Unfortunately, there are times when dryness can set in, where the words and thoughts are devoid of any feelings and detached from the heart, where prayer seems more of a chore than a fruitful experience (CCC 2731). Acedia (sloth) can be another barrier to fruitful prayer, where "the spirit is willing, but the flesh is weak" (Matt. 26:41) (CCC 2733). The solution is not to cease praying, but to continue to pray and seek further conversion, if this is what is needed (CCC 2731).
Prayer can be spontaneous––an informal talk on whatever it is one wishes to pray about, or prayer can be formal––a written or rote prayer that is recited with devotion. The most popular of all rote prayers is the "Our Father", which, at the request of his disciples (Luke 11:1), was taught by the Lord Jesus Himself (Matt. 6:9-15); hence, the "Our Father" is also called "The Lord's Prayer", and is the greatest of all prayers (CCC 2774). At the beginning, it focuses on God. "Our Father, Who art in heaven" means that we belong to God, that He is our Father (Matt. 23:9), and we His beloved children (1 John 3:1) (CCC 2782), and that He resides in heaven, where He wills all his people to spend eternity (1 Tim. 2:4) (CCC 2795-2796). The "Our Father" continues with seven petitions. "Hallowed be thy name" expresses our love and honor for God, and also expresses our desire that He be loved and worshiped by all men (CCC 2807). "Thy kingdom come" expresses our desire that the kingdom of God (the reign of God through the Church) will spread throughout the world, so that the Church will grow in numbers and in influence, touching more and more people with God's grace (CCC 2818). "Thy will be done on earth as it is in heaven" expresses our desire that the people on Earth will serve and obey God as perfectly as those in heaven do, thereby fulfilling God's will and transforming the people on Earth so that Earth resembles heaven (CCC 2825). "Give us this day our daily bread" petitions God to provide us with our spiritual and bodily needs that day (CCC 2830). "Forgive us our trespasses as we forgive those who trespass against us" expresses our forgiveness of others, and our intention that God will forgive our sins because we have forgiven others (Matt. 6:14-15) (CCC 2840). "And lead us not into temptation" petitions God to keep us from all temptations by giving us sufficient grace to overcome temptations of the world, of the flesh, and of the devil (CCC 2846). "Deliver us from evil" petitions God to keep us from all harm, both temporal and spiritual (CCC 2854). We end the Lord's prayer by saying "Amen", which means "So be it". It is by saying "Amen" that we say to everything that we have prayed for, "Let it be done".
One of the best methods of prayer is the "Liturgy of the Hours", or breviary, which consists of hymns, psalms, canticles, spiritual readings, intercessions, and prayers, to be said at various times during the day. These consist of the Office of Readings, Morning Prarer, Daytime Prayer (Midmorning, Midday, Midafternoon), Evening Prayer, and Night Prayer. They come in a four volume set (2 for Ordinary Time, one for Advent and Christmas, and one for Lent and Easter), and there is a smaller, one volume edition, for laypeople who wish to say only morning and evening prayer. Besides the Liturgy of the Hours, one may pray using the Scriptures, to meditate on various passages and readings. The best method is to get a copy of the day's readings (which are the readings that are read that day at Mass). The cycle of Sunday readings repeat every three years, while the cycle of weekday readings repeats every two years. One who reads these readings everyday will have gone through almost the entire Bible at the end of three years, and will have covered all the main parts.