How content changes can affect the site
Depending on how your site is set up, content changes can have a much bigger impact that one page. For example, when you create a News and Media content type, that content will be displayed on the News and Media page and may also be displayed on the homepage (e.g. as part of a list of the three most recent News and Media articles). Unpublishing content could break existing links to that content, adding links as menu items (e.g in the footer links, or in the main navigation) will mean that your new menu item/link is displayed on every page, and new content can also create a link in the breadcrumb menu.