Feed-based page layouts offer a two-tabbed page that allows users to switch between a Chatter feed and a detail page for the record. The tabs are marked as Feed and Details, as shown in the following screenshot:
A prerequisite for feed-based layouts is to enable feed tracking for the object that you wish to create a feed-based layout for. Feed tracking allows users to follow records, which results in feed updates being shown for users whenever the field values are modified. Let's take a look at how to enable feed tracking in the next section.