Do you know that there are only 5 “weekdays”?

And of course the “weekend” has 2 days.

The days of the week come from the Names of mythical figures, so the first letter of each day must be a CAPITAL letter.

Days of the Week:
Monday = associated with the Moon
Tuesday = from the god Tiw, associated with Mars
Wednesday = from Germanic god Odin
Thursday = from Germanic god of thunder Thor
Friday = from Germanic goddess Frigga associated with Venus
Saturday = associated with Saturn
Sunday = associated with the Sun

Weekdays:
Monday, Tuesday, Wednesday, Thursday, Friday

Weekend:
Saturday, Sunday

Here are the abbreviations:

Mo., Mon.
Tu., Tue., Tues.
We., Wed.
Th., Thu., Thur., Thurs.
Fr., Fri.
Sa., Sat.
Su., Sun.