Dates: All time is divided into two segments. The first segment is BTG - Before The Gathering. The second is ATG - After the Gathering. In the current time (1207 ATG), time is only referred to in these terms.
There is one other time era. The Urnati culture prior to the Cataclysm was counting their years on their own scale. So events prior to the Cataclysm may be referred to on that scale, which began more than 10,000 years before the Cataclysm. Anyone alive, however, would refer to it in ATG terms, with the Cataclysm occurring at 3396 BTG (-3396).
The Gathering was an event where the Nine Nations signed an agreement for trade and peace, bringing a relative end to most international strife between nations.
There are 10 days in a week, with the 6th, 7th, and 10th days considered those of rest. There are 20 hours in a day, and many cultures use Base20 for their counting and mathematics.
There are three weeks in a month, and 10 months total, for a total of 300 days in a year.
Seasons are based on the position of the suns relative to the planet, but correspond roughly to 75 days per season.