Klaviyo JS snippet method documentation?

Hello, I was hoping I could get some insight on the methods provided here:
https://developers.klaviyo.com/en/docs/introduction_to_the_klaviyo_object#supported-methods

I am mainly confused about the use case for `account` and `isIdentified`.

I found some more info here:

https://developers.klaviyo.com/en/docs/guide_to_setting_up_api_based_website_activity_events#website-activity

https://developers.klaviyo.com/en/docs/guide_to_integrating_a_platform_without_a_pre_built_klaviyo_integration#javascript-track-api-for-onsite-metrics

The latter links hints that the klaviyo js snippet is just a wrapper to the events api:
https://developers.klaviyo.com/en/reference/events_api_overview

However, when I try to find out more about what kind of events there are, there is not a formal definition. The only event information I can find is on those two pages. I am wondering if I missed a page for a listing of the available events and expected shapes? I could reverse all of this, but it would be easier if we had common event definitions in one page and when to use them.