Psalms

David is thought to have written 73 of the 150 psalms. He was renowned as a musician and, before he became king himself, used to perform for King Saul.
Psalm 3, written by David after the revolt of his son, Absolom, shows how David was protected by God from his enemies:

Psalm 3:4-6
"I cried unto the Lord with my voice,
and he heard me out of his holy hill. Selah.
I laid me down and slept;
I awaked; for the Lord sustained me.
I will not be afraid of ten thousands of people,
that have set themselves against me round about"

The psalm is about Jesus' suffering on the cross, though it was written 1,000 years before his time!

Psalm 22:16-18
"For dogs have compassed me:
the assembly of the wicked have inclosed me:
they pierced my hands and my feet.
I may tell all my bones:
they look and stare upon me.
They part my garments among them,
and cast lots upon my vesture"

The psalm, written by David who was once a shepherd himself, compares the love we get from God to the love of a shepherd for his flock. It ends with the joyous lines:

Psalm 23:6
"Surely goodness and mercy shall follow me all the days of my life:
and I will dwell in the house of the Lord for ever"

The psalm is about sin, guilt and forgiveness. It encourages us to confess our sins in prayer to God.

Psalm 32:5-6
"I acknowledged my sin unto thee,
and mine iniquity have I not hid.
I said, I will confess my transgressions unto the Lord;
and thou forgavest the iniquity of my sin. Selah.
For this shall every one that is godly pray unto thee in a time when thou mayest be found:
surely in the floods of great waters they shall not come nigh unto him"

Nathan was angered by David's adultery with Bathsheeba. David wrote this psalm appealing to God for forgiveness. The first verse of the psalm goes like this:

Psalm 51:1
"Have mercy upon me, O God, according to thy lovingkindness:
according unto the multitude of thy tender mercies blot out my transgressions"

Psalm 89 reminds us that we should always worship God and never stop.

Psalm 89:1-2
"I will sing of the mercies of the Lord for ever:
with my mouth will I make known thy faithfulness to all generations.
For I have said, Mercy shall be built up for ever:
thy faithfulness shalt thou establish in the very heavens"

The psalm is a prayer by Moses from which the often quoted life expectancy of men, 70-80 years, is taken.

Psalm 90:10
"The days of our years are threescore years and ten;
and if by reason of strength they be fourscore years, yet is their strength labour and sorrow;
for it is soon cut off, and we fly away"

Psalm 119 is a prayer about obeying God's commands. The first stanza, whose 8 verses each begin with the Hebrew letter Aleph, goes like this:

Psalm 119:1-8
Aleph
"Blessed are the undefiled in the way,
who walk in the law of the Lord.
Blessed are they that keep his testimonies,
and that seek him with the whole heart.
They also do no iniquity:
they walk in his ways.
Thou hast commanded us to keep thy precepts diligently.
O that my ways were directed to keep thy statutes!
Then shall I not be ashamed,
when I have respect unto all thy commandments.
I will praise thee with uprightness of heart,
when I shall have learned thy righteous judgments.
I will keep thy statutes:
O forsake me not utterly"

One of the Songs of Degrees, Psalm 134, has only three verses, however it is not the shortest chapter in the Bible. Psalm 117 has only two verses!
Here is Psalm 134 in full:

Psalm 134
A Song of degrees.
"Behold, bless ye the Lord, all ye servants of the Lord,
which by night stand in the house of the Lord.
Lift up your hands in the sanctuary,
and bless the Lord.
The Lord that made heaven and earth
bless thee out of Zion"

This last psalm tells us to praise God in as many ways as we can.

Psalm 150
"Praise ye the Lord.
Praise God in his sanctuary:
praise him in the firmament of his power.
Praise him for his mighty acts:
praise him according to his excellent greatness.
Praise him with the sound of the trumpet:
praise him with the psaltery and harp.
Praise him with the timbrel and dance:
praise him with stringed instruments and organs.
Praise him upon the loud cymbals:
praise him upon the high sounding cymbals.
Let every thing that hath breath praise the Lord.
Praise ye the Lord"