When input is gathered, it is bypassed to remote execution handler on server when some code performs an action. The result of the action is then returned back to editor as an output parameter of certain type. You can select from following types of your output:
Nothing is being done. You usually just want to execute external server code and don't want any result.
If your input parameter was a selection, the resulting output will replace currently selected text in the editor.
Output is being transformed into fully functional snippet that is inserted at active caret position. This is probably the strongest and coolest feature so far. Imagine dynamic snippeting based on current state of your source code. Refactoring taken into another level.
Output, formatted as an HTML document is shown in the popup window. There are special link types that can access active document (such as going at specific line and others).
Resulting output is displayed as a tooltip below caret. Tooltip text can be HTML formatted.