ServiceNow is a platform-as-a-service (PaaS), not a SaaS, that allows development of new products on top of it.

At its core, there is a workflow management engine that third parties can use to implement their own, stateful, process centric products and services.

We have ServiceNow proper (the CRM) and a completely unrelated to CRM third party product that we have purchased and which is implemented on the ServiceNow platform. Both have nothing to do with each other and are used by different business users.