I've offended people by pure ignorance. Because of that I love to hear about different cultures and I'm hoping to learn a lot of neat things on this thread.
I speak a dialect. Where I'm from calling a female, women or child, gyal (girl in english) is common everday communication. My dialect is close to the Jamaican's dialect. Calling any Jamaican girl or woman by that term is calling her a good for nothing dirty person. Learned that through my wonderful Jamaican friends.
A friend of mine told me that growing often he would hear his father say, "I'm gonna Jew you". It was not until he was an adult that someone brought it to his attention the term he was using was derogatory. He had never given it any thought.
Growing up I learned that it was bad manners to belch. The Amish, however, especially the men, belch really loud at the end of their meal. It shows their wives that the really enjoyed the meal.