Corrective maintenance process or work flow

Hi SAP Gurus,

I have to make a process of corrective maintenance.I have some queries against it:-

1) Difference between breakdown & corrective maintenance ?

2) what are the steps of process or workflow of corrective maintenance?

3) what are prerequisites?

4) what are the reports and does we get the MTTR/MTBR of this process.

Please share your valuable experiences

Thanks

Gaurav Solanki