This document area is where you can create or edit the items that are used to populate your group's home page.
The "Main Group Widget" document stores the content that displays in the main top/middle of the page
The "Group Intro Widget Content" is where you can upload your logo, and insert a statement about your company, who you are, what you do, etc.
The "Featured Video Widget" is where you can insert a video file (YouTube, or other) that will appear on your home page - it can play in situ or - depending on the video type you insert, like YouTube for example - visitors can also click to view the video in full screen, or go to the main video display page.
Any additional content you create here, if you click to "feature" it will appear in the featured content carousel directly below your main content section.
There is an example Featured Content item here you can edit, copy, etc.