What are the applications of superconductor that world is directly benefited from?

Superconductors

In this project you have to do research about superconductors. During this project you will search online material about superconductor for finding the answers to the following questions,

1. What is the superconductor and when it was discovered?

2. What are the advantages of the superconductors?

3. What are the applications of superconductor that world is directly benefited from?

4. What are the key challenges in their deployment for large scale applications?