To revert to the latest version of your site:
You can find the Revert button by going to your Dashboard, clicking Activity, and then choosing Revert Changes.
Clicking the Revert button removes everything since the last time you pressed Publish. It's definitely a button to be careful with!
For those of you working with a team or a group, we might suggest having them individually delete items they'd like to remove, rather than using the Revert button. This will eliminate the chance of accidentally deleting another editor's work if you have multiple people editing the website.