It shows you a graphical map of how a conversation object works if you pick it in your scene. Originally you had to create a new interaction for every time the character picks a dialogue a line, so it was a lot of different objects and this editor shows how they connect.
I prefer the ActionList method of conversations which keeps everything inside a single cutscene object. It's way easier to work with.
Indeed: it's actually rather unnecessary now that the "Override options?" feature exists within the Conversation Action.
The Editor was created before that feature was possible, and was intended as an easier alternative to the Conversation Inspector. However, running all Actions within the same ActionList (using the ActionList Editor) is now the recommended way of working with Conversations.
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I prefer the ActionList method of conversations which keeps everything inside a single cutscene object. It's way easier to work with.
The Editor was created before that feature was possible, and was intended as an easier alternative to the Conversation Inspector. However, running all Actions within the same ActionList (using the ActionList Editor) is now the recommended way of working with Conversations.