Builder
From uCoz Wiki
Builder allows to easily add/edit blocks on your website and change their display order in visual mode.
By means of this feature you can quickly select content for your blocks - scripts, widgets, menus, video, audio, RSS, HTML code.
This feature is installed by default for all new websites.
If your website was created before the global update you can enable Builder for the website design customization in Control Panel -> Common settings -> Use "Builder".
Example of Builder usage at http://maps.ucoz.com/
