The introduction of CKEditor 5 will bring major changes for Sector 10 and sites updated from Sector 9 to 10! CK5 is a complete re-write and some of the CK4 features are moving into a paid premium version.
Sector AdminUI toggle allows editorial users to hide the AdminUI overlays from 'view draft' and 'view revision' node views, allowing a better preview of content prior to publication.
The Page content type is used for pages that are in your menu structure - you can easily move these pages around the menu (even changing their level) and there are plenty of display settings for you to customise how they look.
TL;DR stands for too long; didn’t read. The editor guides on Sector.nz contain a large amount of information - here are the most important things to know.
Once you've logged in to your user account, you'll see the Administration User Interface (AdminUI). This has two distinct areas: the AdminUI overlay on the frontend of your site, and the AdminUI backend.