Revisions is a post type and a feature in WordPress. It enables WordPress to automatically save revisions of your posts, pages, or custom post types after every 60 second while a user is working on them. Revisions were added in WordPress for two very important reasons. One of them was to prevent the risk of losing data. Computers are weird and unpredictable. You never know when your browser will crash or if your computer will restart automatically. There are also situations when you accidentally close the browser window or refresh the page. Sometimes even the electricity goes out during a stormy weather. In the old days of WordPress, the problem was that you would simply lose all the work that you didn’t save. Well thanks to Revisions, you don’t have to constantly save everything. WordPress does it for you, so you don’t lose any data during catastrophic events like the ones we described above.
The other important reason for adding revisions was to improve the editorial workflow. There are times in writing when you make mistakes or get rid of an entire idea without thinking it through. A day or two later, you want to go back to that initial idea. Well revisions allow you to compare your post versions. You can even restore an older version of your post if you like.
Revisions autosave interval can be managed by defining
WP_POST_REVISIONS in your wp-config.php file. You can choose to save revisions every 30 seconds, every 2 minutes, or anything else that you like. You can even turn it off completely. There is a myth that turning off revisions will improve your site’s performance. It is NOT TRUE.