Thanks for information Rick & Art.

A little further digging found the following definition of a CI:
"Any component or other service asset that needs to be managed in order to
deliver an IT service. Information about each configuration item is recorded in a configuration record within
the configuration management system and is
maintained throughout its lifecycle by service asset and
configuration management. Configuration items are under the control of change management. They
typically include IT services, hardware, software, buildings, people and formal documentation such as
pr
ocess documentation and service level agreements."
https://www.axelos.com/Corporate/media/Files/Glossaries/ITIL_2011_Glossary_GB-v1-0.pdf

Hopefully someone is able to make sure I just didn't miss-understand what was said in the episode, or adds a correction if needed as it certainly confused me.