Maybe its because there's a rumor that there's a U2 album out there that is based on these Psalms but I have always loved the Psalms that go from 120-134 which are entitled "Songs of Ascent." There are a lot of ideas out there about what they were "for" but the most common one is that they may have been the songs that the people would sing as they would be ascending the hill into Jerusalem for feast days.