YouTube”s exploring functionality in the full-screen video player allows users to directed exploration of related videos.

1) Clicking the explore button in the lower left brings up related videos visualization, which is sort of like a digraph that looks like a constellation of stars.

2) Circles in the center are videos. Hover over one circle expands to show you other videos related to that one, forming a cluster. Click a circle to watch a video.

3) Circles in the upper left corner indicate the clusters you”ve explored. Clicking on a circle returns you to the related constellation, focused on the cluster you click. Constellation shows the path back to the original video–what relates the video you”re now watching to the video that started your exploration.

1. Exploration of related videos
2. Constellation after watching 2 related videos

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