I try reading the ingame descriptions of two songs that confuse me. First is the level 1 song (I can't remember the name). The first song says that it "increases combat effectiveness" or something along that lines. The level 5 (or is it 6?) song, Tymora's Melody increases luck.

I have no idea what these two songs actually do, in the game though.

If my Bard is going to be singing, which song is more effective?

TIA