In Sitecore Experience Accelerator (SXA), the concepts of Partial Designs and Page Designs are fundamental to creating reusable presentation elements. They allow you to efficiently structure the design of your web pages, and they make it easier to manage changes across a large site.
Partial Designs are reusable pieces of layout. You can think of them as sections of a page. For example, you might have a header partial design that includes your site logo, main navigation, and search bar. You could have a footer partial design that includes copyright information, secondary navigation, and social media links.
These Partial Designs can be reused across multiple pages. If you need to make a change, like adding a new element to the header, you only need to make that change in one place and it will be reflected on all pages that use that Partial Design.
Page Designs are essentially combinations of Partial Designs. They define the full layout of a page by specifying which Partial Designs to include and in what order.
For example, a typical Page Design might include a header partial design at the top, a footer partial design at the bottom, and one or more content partial designs in between. When you create a new page, you can simply select a Page Design, and all the associated Partial Designs will be automatically included.
This system allows you to manage your page layouts more efficiently, as changes to a Partial Design are automatically reflected across all Page Designs that use it. It also provides a great deal of flexibility, as you can create a variety of Page Designs to suit different types of pages while reusing common elements.