Hi all,
Today, I will be talking a bit about 六曜 (ろくよう).
六曜 is used in modern Japan to describe whether it is ok to do something or not. Originally, it was used in China to break up the time into 6.
When you visit a weather forecast website such as https://tenki.jp, when you go into the individual areas, you will see something like this.

The following are the 六曜 [ろくよう]. These are being used to describe whether it’s ok to do something or not ok to do something.
「先勝/せんしょう」「友引/ともびき」「先負/せんぷ」「仏滅/ぶつめつ」「大安/たいあん」「赤口/しゃっこう」
先勝 : Better to do things early. Before lunch is ok, after lunch is bad to have events
友引: OK to have weddings. Morning is OK, 12pm is bad, Evening is ok to have events
先負: Bad to do things before lunch, but ok to do things after lunch
仏滅: Bad to do everything but ok to do things like funeral, to end a bad relationship
大安: OK to do everything
赤口: Bad to do everything
Source: https://tokubai.co.jp/news/articles/1563
Have a great Wednesday ahead!
/Can