Medieval towns did not have cathedrals in them. In the earlier parts of the Middle Ages, the defining feature of a city was the presence of a cathedral. Later, a town could also become a city by...
A few that come to mind are: Notre Dame de Paris Canterbury Cathedral Ely Cathedral Cathedral Church of St. Paul in London Salisbury Cathedral Winchester Cathedral Bangor Cathedral St. David's...
I have never heard this term used, but if it has been it is because the churches contrained windows that told the stories of the bible. People couldn't read so the church to teach the bible stories...