Website bounce rate: The percentage of people who land on a page on your website and then leave without clicking on anything else or navigating to any other pages on your site. A high bounce rate generally leads to poor conversion rates because no one is staying on your site long enough to read your content or convert on a landing page.

Email bounce rate: The rate at which an email was unable to be delivered to a recipient’s inbox. A high bounce rate generally means your lists are out-of-date or purchased, or they include many invalid email addresses.