The Publish option allows the developer to quickly deploy a Knowledge base, primarily for the purpose of testing and review by others. Each published knowledge base has a unique and persistent url. Please note that a knowledge base deployed via Test Run (F9) shares their 'transient' url with all other knowledge bases that undergo Test Run from the developer's account.
There are two ways of publishing one via the shortcut toolbar in the editor:
Via the Publish icon on the tool bar
Alternatively use the Publish option via pull down buger menu
The difference between the two methods of Publishing is that the toolbar approach carries out a publish action before displaying the Publish dialog.