Here you can specify the content of the issue. It is necessary to enter an e-mail subject into the Subject field before you can save the changes. You can add macros to the body or subject with the aid of the Insert field section that will be resolved into the data of the appropriate subscriber.
More resources can be found at:
Page url: http://devnet.kentico.com/docs/5_5r2/contexthelp/index.html?edit_tab.htm