A layout is a set of pages visible to the users in a certain role.
A layout contains information about the layout of the pages it contains and the preferences defined for those panels.
A page contains one or more panels. You can group related panels in a page. For example, you may want to create a separate page to group all the panels you need to participate in a certain process.
The available pages are displayed like tabs, each tab is identified by the label of the page. You can select which page you are currently viewing by clicking on its corresponding tab. If the layout contains only one page, the tab is not shown.
You may see several layouts at the same time if you are assigned to different roles, or if several layouts are assigned to the your role.
Oracle BPM WorkSpace comes with a Default layout that is only available to the logged in user. The default layout contains a single page labelled Default. If this is the only page in the layout, then the tab for this page is not visible. If edition is enabled you can modify this layout by adding pages or adding components to the current pages.
The changes you make to the Default layout are only available to you. If you need to make changes to the default layout and make them available for all the users of WorkSpace, then you need to export the layout and then configure WorkSpace to use this layout for the Default layout. For more information, see Oracle BPM WorkSpace Default Layout Customization.