A skin is the border around each portlet within a portal page. Unlike themes, which apply to the overall look and feel of the portal, skins are limited to the look and feel of each portlet that you insert into your portal application.
By default, only a limited selection of skins are available for each theme.
There are several options for working with skins:
In addition to using the pre-made skins that came with the installation, you can use the New Skin wizard to create customized skins for your project.
By opening a theme in Page Designer, you are also able to edit the skins that are associated with that theme.
By using the Properties view for a skin, you can change the default skin for your portal project. You can also define the default skin of a theme within the Properties view of that theme.
To view changes to your theme and skins JSPs without restarting the portal server, you can force the test server to automatically check for new versions of JSPs after deployment of theme and skin files. For more information, refer to Optimizing JSP file testing.