Callouts highlight key details so people don't miss them.
Use a callout when people need to notice something, like a tip, a requirement, or a key detail.
Use a callout when content organization alone isn't enough. Where something sits on the page already signals its importance. Content covers how to organize and order content so the most important information comes first.
Keep callouts short. One or two sentences works best. If you need more space, the information probably belongs in the main content.
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<strong>Guide</strong>: <a href="https://www.library.upenn.edu/services/books-mail">Set your address with Books by Mail</a>
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