What was the key currency (money) used in the Middle Ages

one way people would buy items in the middle ages is by bartering

Explanation:

This is exchanging an item/items for goods and services.

This was a commonly used method of trade in that time period

honestly i love the walking dead, mainly the quotes. “well, pardon me young man, excuse the [insert bad word here] out of my gosh darn french, but did you just threaten me? ” sksk (of course it's not the exact words)

martin luther believed that selling indulgences was wrong and gave people a license to sin. the roman catholic church used the practice of indulgences to raise money for major building projects.