The PageCatalogPart control serves one very specific purpose on a Web Parts page: it acts as a page catalog to maintain any controls previously added to the page that a user has closed, so that the user can add them back to the page. This control is visible only when a web page is in catalog display mode, a special view that enables users to add and remove controls on the page. Add a PageCatalogPart control to your page if you want to provide users with the flexibility of closing and reopening controls. If your page does not allow users to close controls at all, there is no need to add a PageCatalogPart control to your page.
The PageCatalogPart control, like all other CatalogPart controls, resides in a CatalogZone zone.
Drag the PageCatalogPart control from the Toolbox panel to a CatalogZone control on the page.
For an overview of and programming examples for the PageCatalogPart control, see PageCatalogPart Class in the MSDN library.
For a full description of all PageCatalogPart control properties, see PageCatalogPart Properties in the MSDN library.