Info for Beginners:
In Civ V you could build almost every building in a city, a library, a workshop, an amphitheater…all of them. Well in Civ VI this is not the case. Most buildings have to be built in a district. So to build a library you have to build a campus, if you do not have a campus you can not build a library.
So what this image is showing is the bonuses you get depending on where you put your districts.
Remember you can still only work 3 tiles out from the city so building a city with every district is probably not going to happen. So in Civ VI you are going to need to focus your cites on certain things and this image can help you determine where to place districts and what districts to use in a city.
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