Classification of the Psalms: 
"There have been numerous attempts to classify the psalms. Though each psalm is an individual poem with its own theme, there are enough noticeable shared forms and ideas to warrant categorization. The following classification is based partly on form and partly on content:
"There have been numerous attempts to classify the psalms. Though each psalm is an individual poem with its own theme, there are enough noticeable shared forms and ideas to warrant categorization. The following classification is based partly on form and partly on content:
 1.      Lament Psalms contain a plea for deliverance or defense and are addressed directly to God.  They may be individual (Chapters 5-7, 13, 17, 22, 25, 26, 28, 31, 35, 36, 38,  39, 42, 43, 51, 54-57, 59, 61, 63, 64, 69-71, 86, 88, 102, 109, 120, 130,  140-143). Or national (Chapters 12, 44, 58, 60, 74, 77, 79, 80, 82, 83, 85, 90,  94, 106, 108, 123, 126, 137).
 2.      Psalms of confidence include a lament, but the ideas of security, peace, joy, and confidence  predominate. They may be individual (Chapters 3, 4, 11, 16, 23, 27, 62, 121, 131  (or national (Chapters 115, 125, 129).
 3.      Songs of Thanksgiving express public thanksgiving for what God has done or in anticipation of what He  will do. They may be individual (Chapters 9, 10, 30, 32, 34, 40, 41, 92, 107,  116, 138), or national (Chapters 65-68, 118, 124).
 4.      Psalms of Praise are constructed around three key elements: a call to praise or introduction, a  cause for praise (usually for God’s attributes or deeds), and a conclusion  (Chapters 8, 19, 29, 33, 100, 103, 104, 111, 113, 114, 117, 135, 136, 145 –  150).
 5.      Enthronement Psalms of the Divine Kingdom contain the expression “the Lord reigns” (or, in the case of Psalm 98, “the  Lord, the King”), and speak of the rule of God over all the earth. They are  prophetic of Christ’s kingly rule (Chapters 47, 93, 96 – 99).
 6.      Songs of Zion extol Zion, or Jerusalem, for its exalted role as the abode of God’s glory and  as the religious and political capital of the nation (Chapters 15, 24, 46, 48,  50, 76, 81, 84, 87, 95, 122, 134). The Pilgrim Psalms (see below), are sometimes  included here, but they do not really constitute a distinct literary type.
 7.      Royal Psalms concern the reign of the king, either historical or messianic, or both (Chapters  2, 18, 20, 21, 45, 72, 89, 101, 110, 132, 144).
 8.      Wisdom Psalms emphasize the traditional teaching of the wise men of Israel: meditation of the  law, the way of the righteous versus the way of the wicked, and the necessity of  practical righteousness (Chapters 1, 14, 37, 49, 52, 53, 73, 75, 91, 112, 119,  127, 128, 133, 139).
 9.      Historical Psalms trace the history of God’s saving activity on behalf of Israel (Chapters 78,  105).
 Other categories, identified strictly for content, overlap with the above. These  include the following:
 1.      Messianic Psalms are prophetic in some way of the Messiah. They include psalms in which the  righteous man’s character is a type of Christ (34:20; 69:4, 9), the righteous  man’s experience foreshadows Christ’s experience (22), the existing  king’s ideals and calling will be fulfilled in Christ, the ultimate King  (Chapters 2, 45, 72), Christ’s work is prophesied with no contemporary reference  (only 110), or the enthronement of Christ as universal King over the  earth is predicted (Chapters 47, 93, 96 – 99).
 2.      Imprecatory Psalms contain an imprecation or prayer for retributive justice to fall on one’s enemy  (Chapters 35, 55, 58, 59, 69, 83, 109, 137, 140). These may be justified by  remembering that the Israelites were building a political kingdom and, as long  as evil men triumphed over them, God’s rule was thwarted. The psalmists were  concerned primarily with the glory of God, and at the very least, they did put  the matter into God’s hands for His just dealing. These prayers are actually in  the same spirit as the petition “Thy kingdom come” (Matt. 6:10), because the  coming of God’s kingdom includes the destruction of the wicked (see the note on  Psalm 109).
 3.      Psalms of Ascents  or Pilgrim Psalms (Chapters 120 – 134), were sung by pilgrims journeying up  to Jerusalem for the three annual feasts of Passover, Pentecost, and  Tabernacles.
 4.      Acrostic Psalms are those in which each verse begins with a consecutive letter of the Hebrew  alphabet (Chapters 9, 10, 25, 34, 37, 111, 112, 119, 145). Psalm 119 is in a  class by itself with eight verses for each letter of the alphabet. 
Superscriptions in the Psalms: 
 The identification of many of the technical words in the superscriptions is  dubious. The headings include names for types of psalms (“a psalm”), musical  terms (“to the chief musician”), melody indicators (“upon Shoshannim”, 45), and liturgical indicators (“for the Sabbath day”, 92). Fourteen  psalms contain historical superscriptions that give some brief mention of the  occasion on which the psalm was written (Chapters 3, 7, 18, 30, 34, 51, 52, 54,  56, 57, 59, 60, 63, 142)."
BooksOfTheBible
[[A Psalm or Song for the sabbath day.]] 
It is a good thing to give thanks unto the LORD, 
and to sing praises unto thy name, O most High:
Psalm 92:1
