Using the Sort By option in the Document List view allows you to sort through the content in the main list that appears in the center section. For any sort, you can choose the order—for example, oldest to newest (or vice versa) or A to Z (or Z to A).
When you’re showing All Documents, you can Sort By:
Date Modified
Title
Author
If you select the Proposals filter from the lefthand panel, you can Sort By: