I would like to know if there is a common abbreviation for days of the week in a two letter form.
I mean: Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday; can be abbreviated as Su, Mo, Tu, We, Th, Fr, Sa? Is this the common form?
Note that I have also seen Sn for Sunday, and some times St for Saturday (but I think less frequently).
It will be used in a tabular data program to show information about free work days of employed and each column can't have enought space to include full week day name.
For "common form" I mean, what are the abbreviations that is more used in programs.