Days of the week in Japanese

I've finished posting the days of the week now in the 30 days of Kanji series I'm currently doing. I decided I would add an extra Kanji to my studying since it's useful and completes the use of the previous 7 Kanji for using to write the full weekday names. This is the Kanji I mean:
曜 - よう - weekday
http://jisho.org/kanji/details/%20%E6%9B%9C

As a compound word with another Kanji I've learnt we get:

曜日 - ようび - day of the week
http://jisho.org/kanji/details/%E6%9B%9C%E6%97%A5

Below are all 7 days of the week using the full Kanji. Each day links to the previous post on this site.

日曜日 - にちようび - Sunday
月曜日 - げつようび - Monday
火曜日 - かようび - Tuesday
水曜日 - すいようび - Wednesday
木曜日 - もくようび - Thursday
金曜日 - きんようび - Friday
土曜日 - どようび - Saturday

N.B. While looking at the meanings of the days of the week I noticed that there are similar Kanji and I currently don't really know when one or the other would be used. Each Kanji I have learnt seems to mean the day on its own but can also be used with 曜, and then they are also used with 曜日. One reference I did noticed on jisho.org was that they referred to the shorter version as Abbreviations.

N.B. Also in this post there is weekday (曜) and day of the week (曜日). I wonder if in Japanese it has the same use to split the weekdays (Monday-Friday) and weekend (Saturday and Sunday).