Bookmarks are topics and answers that you have saved. Bookmarks allow you to quickly access a feed of questions and answers about the topic and easily go back to answers you have saved.
On web, you can find bookmarked Topics andby clicking on your profile image at the top right-hand corner of the site and selecting "Bookmarks" from the drop-down menu.
On the mobile app, you can find them by selecting the "Home" button on the top left-hand corner of the app and selecting "Bookmarks" from this drop-down menu.
You may also visit https://www.quora.com/bookmarks.