What is the difference between "rights" and "privileges"?

It’s my opinion that “rights” are things that are your due just for being there, but “privileges” are things that are earned. I’d like to know your take. Here are some things to consider:

1. I’ve heard that marriage is a privilege, not a right, but I didn’t really do anything to earn my privilege to marry. We just did it.

2. I’ve heard that some things like health care and food are “rights,” but in nature, these things don’t just appear before you to feed and care for you – someone, like a doctor or farmer, must “earn” them by their work. So these sound like privileges to me.

3. Are rights the things that are granted by an authority (like a government), and the things not thereby granted are not rights, or are rights things that are inherent and if they are not granted by the local authority, that authority is violating rights?

4. Is a right something that you are entitled to (like health care or marriage, for example), or is it simply your right to be free to pursue things (like a job, to pay for health care) unhindered?

(For what it’s worth, this is NOT HOMEWORK. It’s just a topic that came up at lunch today and I remembered to ask the Collective later.)