What Is Usenet?
Imagine, if you will, a vast publisher of newspapers. These newspapers cover every topic under the sun; from gardening to writing science fiction to digital music to computer programming. That's what Usenet is; a collection of newspapers, called "newsgroups."
What's different about newsgroups, compared to newspapers, is that anyone can write an article for any of these newsgroups. And more importantly, anyone can respond to any article by writing an article of their own. Think of it as a very large "Letters to the Editor" section. Most new articles are requests for help or declarations of opinion, whereas most responses try to answer, clarify, or offer the author's own opinion on the original article.
Informant is quite a bit different than most newsreaders, mostly because it can show you different views of discussions that you're interested in. As a result, it's important to be able to easily jump to the different views within Informant. Thus, the first thing you see when starting up Informant is the Manager.
Unlike most managers, this one is useful. The Manager lets you get to any of the major subsystems of Informant. From the Manager, you can click on the "Front Page" button to go to your Front Page (a customizable view of whatever discussions you want to keep track of), you can click on the "Subscriptions" button to go to a list of subscribed newsgroups, you can click on the "Settings" button to view or change your preferences, or you can go directly to any newsgroup that you're subscribed to.