The launch history is a list of the most recent debug launches. Favorite debug configurations are launch configurations that you set to be favorites.
When you are creating a launch configuration, you can choose to have it added to the favorite debug configurations list by way of the Common tab in the Debug launch configurations dialog box. You can also modify favorite debug configurations and the launch history in the workbench preferences where, in the Preferences dialog box, selecting Run/Debug > Launching will open the Launching page. In this page, you can set a variety of launch settings, including the number of launch configurations that will be displayed in the launch history.
In the workbench, the launch history and favorite debug configurations are displayed together when you select the workbench toolbar Debug push button menu or when you choose Run > Debug History from the workbench menu bar. If you have set favorite debug configurations and a launch history exists, then the launch history and favorite debug configurations are displayed together with a separator in between and favorite configurations listed on top. If there are no set favorite debug configurations, then only the launch history will be displayed. If there is no launch history (or if you have chosen to remove all items from the launch history), then only the favorite debug configurations will be displayed.
To relaunch an entry in the launch history or favorite debug configurations list, select it from the list that is displayed when you select the workbench toolbar Debug push button menu or when you choose Run > Debug History from the workbench menu bar.