Tell us more about Hajj & Umrah

I thought it would be good to know more from Muslims about Hajj and Umrah. So I would be happy to see the contribution of many Muslims but also non-Muslims, in order to be able to understand better why and how Muslims perform Hajj/Umrah.

Here some questions for the Muslims:

- Why do you have to perform Hajj/Umrah?
- What is the difference between Hajj & Umrah?
- What do you have to do during Hajj/Umrah?
- Why is it so important to perform Hajj/Umrah?
- Did you perform Hajj/Umrah until now?
- Did you perform it more than once?
- What about those who do not have the money for that?
- Why do you have to kiss the black stone at the Ka'bah?
- Why are your sins forgiven if you perform Hajj/Umrah?

If anyone has any other good questions, please add them to the ones above.

Please do not just post links (like Wikipedia) that talk about Hajj/Umrah. Sure you can find all the info about that topic in the net, but I'd like this to be a discussion where we can learn and understand better Muslims and their faith.

Can't wait to read your answers.