Day Pillar
The pillar of your birth day: your Day Master above, and below it the branch read for your closest relationships.
In one sentence
The pillar of your birth day: your Day Master above, and below it the branch read for your closest relationships.
How it is used
There are sixty possible day pillars, and Korean readings often open here because the character that stands for you and the branch traditionally called the spouse palace sit in the same pillar. It is the most quoted pillar and so the most over-read: one pillar out of four cannot carry a whole chart. For births in the hours around midnight, schools disagree about which day the pillar belongs to, so a careful reading names the convention it used.