The Sidebar is the column to the right of this text. Various things are displayed in it including adverts and tables of contents. It can also be customised to fit your needs, simply and easily though is for members only.
Click on the 'My Home Page' link to access your private area. Now create a page called 'sidebar'. The best way to do this is by editing your home page and adding a link like this:
Now edit your sidebar page and add whatever you like. Anything you put on this page will appear in the sidebar on all pages. However, it is only 170 pixels wide so it is not suited to displaying large images or blocks of text.
The best use of the sidebar is for adding links to your own personal favourite wiki pages.
Each section or namespace of the wiki can have its own sidebar and it works just like the personal sidebar. Simply create a page called 'sidebar' in the namespace. For example this link will create/edit the sidebar for the open area:
and this would create one for the cards namespace: