I want to clarify that you mean you don’t understand the term
entity_id (the word shown within a “box”) shown here?
You linked to a page explaining the
automation.turn_on service. It describes how to use this service. Effectively you linked to a dictionary’s description of a word. How to use that “word” is described in another chapter of the documentation (specifically the one for Automations)
The documentation answers your question here, in the Advanced Configuration section, Splitting your configuration
The examples page is part of the documentation, just on a separate page.
You do realize of course that everything related to a single topic cannot be incorporated in the same page because that would make it difficult to read.
I grant you that ‘domain’ is a term that is not well documented. The only place i know where it is mentioned is in the description of the State Object and even that is an indirect reference (because the topic is the State Object, not specifically ‘domain’).
Those specific references to domain and entity_glob appear to be from the Homekit integration. An integration’s documentation is limited to explaining its operation and configuration, not to explain the fundamentals of Home Assistant and its terminology. Nevertheless, it does provide a reasonable explanation for the use of
Perhaps it could have included something similar for its explanation of
Domains to be included. Example:
The documentation is composed by the community. It’s constantly evolving, shaped by the contributions of volunteers. If you encounter anything that you feel could use improvement, you are free to add to it. Your submission is vetted before it becomes part of the official record.