Sidebars : Global sidebars will set the chosen Sidebars on all examples of the chosen page/post type. You can enable global sidebars for each different post type on your site such as pages, portfolio posts, blog posts, and the search results page. Use this when you want every page of that post type to show the same sidebar.
IMPORTANT NOTE: Category and Archive pages do not have this option because they do not have individual page options like other pages.