Some people make money on YouTube through the ads that appear before their videos. YouTubers sign up for an AdSense account through Google, which tracks how many impressions a video gets. An impression is counted as any time the video is watched by a viewer for longer than 30 seconds. AdSense income is based on the number of impressions, which ads are shown during the video, and how many times the ads are clicked. Payments are sent when an AdSense account reaches $100.