The main Workbench canvas displays the connections between the readers (source data), transformers, and writers (destination data). By default, it is the largest area of the workspace on the right.
After you save what you are working on, the workspace name is displayed in the window’s title bar. Here's what an example workspace looks like, with the addition of a few customizations, like transformers, bookmarks and annotations:
SourceSansPro-ExtraLightItalic.ttf