Take the 2-minute tour ×  Any book of zemiros whether it's a
siddur, birchon, or what have you divides the zemiros between
the three meals. Sometimes the rationale is obvious as with the
tikkunim which are written for each meal. Sometimes they seem
arbitrary like Kah Ribbon. My question is twofold:    1. Who
decided on the placement of the zemiros?   2. Is there a unified
set of rules for what makes one song a "night zemer" and another
a "day zemer?" share|improve this question FWIW, Sepharadim do
not follow the same set of "rules" (if you can call them that)
as Ashkenazim when it comes to which Zemiroth are sung at which
meals. –  Seth J Nov 9 '11 at 22:27 Especially since sephardim
have a different collection of zemiroth for the shabbat table in
general with a pretty small overlap with ashkenazim. In my house
we sing which ever ones we feel like from either set regardless
of which meal we're at –  Yitzchak Nov 9 '11 at 23:21 This
doesn't answer your question, but it's interesting nonetheless:
link. Possible