Ever Wonder??

Do you ever wonder why life is what its like, eg why is grass called grass or why is the sky up, who chose the words to say that above us is up -why was the word down not chosen im not sure, but over time i have had some questions ive always wondered answered.

Below is some of what i have wondered:

.....................................................................Why are traffic lights Red, Amber and Green, why was green chosen as the colour go, I can understand red, as to me Red means danger, but the others im not to sure, i found out the answer to this a few years ago and thought others might wonder as well
Green is calming to us, probably because it is prolific in nature and a sign of health and abundance, so it might have lent itself to mean "go."
Amber is associated with warmth, happiness, and the sun. Despite these connotations, it was chosen to symbolize "caution."

....................................................................Who named the Planets -They believed that each of these celestial bodies influenced a particular day of the week.

...................................................................Why is there a leap year and why 365 days in a year - Leap years are needed to keep our calendar in alignment with the earth's revolutions around the sun.

..................................................................Why do some people have curly and some straight is there a reason - the position of the hair bulb in the hair follicle, the way the large bundles of keratin are arranged within each hair shaft.

.................................................................Why do people have different coloured skin (no im not being racist, each skin colour is beautiful in its own right)- my belief is cause of the country people live in and the amount of sun and cloud, people with darker skin live in countries that are hotter and have more sun, so the skin dosent get as much dammage, where people who have white skin live in countries that have less sun and get sunburnt easily.

The one question i cant find an answer for at the moment is why is a window called a window, does it have something to do with the wind, and a window has dow in it??
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