The YouTube feature that lets creators add chapter markers is called Video chapters. It divides a longer video into labeled sections so viewers can jump directly to a particular topic, scene, lesson, or segment.
Creators generally create chapters by adding a sequence of timestamps and titles to a video’s description. The first timestamp must begin at 00:00, and a valid chapter list needs at least three timestamps in ascending order. YouTube then displays the sections along the progress bar and may show chapter titles and preview information.
YouTube introduced the feature in 2020 for desktop and mobile viewers. Automatic chapters were added as an optional extension, using machine learning to estimate sections from a video’s content. “Timestamps” are the markers used to define chapters, but they are not the name of the feature itself; Cards and End screens are separate tools for links and recommendations.