Need more details on Rapid setup

Trying to understand the rapid setup on how to implement.

Currently, LCM provisioning is enabled in my project, once triggered custom business process will be called to proceed further.

What makes difference between LCM Provisioning and Rapid set up?

Requirement: Through SCIM API create identity and invoke Rapid setup. No need of separate application to be onboarded for this.

Can you give some examples and throw more lights on it?