The main advantage to PBworks is that pages can be edited through the browser with a simple click of the pencil button which launches the page editor.  If the edit link is not visible for a page in the upper right corner, that's because you are not logged in with an account that has permission to edit the page.  

When you are done with your edits, click the "Save" or "Save and Continue" button at the bottom of the editor to apply your changes to the page.  These buttons will only appear when the page is being edited.

Click here for more information about all the functions of the PBworks Editor