A "Psalter" is a book or collection of the Psalms, which are sacred songs or hymns found in the Bible. Traditionally, it is used in Christian and Jewish worship, providing prayers and praises to God. The Psalms express a range of emotions, from joy and gratitude to sorrow and repentance. Psalters can vary in format, including printed books, manuscripts, or even digital versions. Many Psalters also include musical notations, allowing for the singing of the Psalms. They have played a significant role in both personal devotion and communal worship throughout history.