A comment is a text string that can be added to any zip file. You can add, amend or view a comment in two ways.
Open an existing archive from the archives tab and on the archives menu, select 'comment', or press control+C. In the comments window you can now view the comment. Click exit to close without making any changes, or type some text into the window and click change.
You can also right click an existing archive and select comment from the context menu. To do this you will need to have set the file associations for Zip Backup from the options menu.