An impression on YouTube is a metric that counts towards a videos performance statistics. It is counted every time a video thumbnail is at least 50% visible on a users screen for over 1 second on YouTube. Impressions are limited to thumbnail views only and do not include video clicks or views. Impressions are counted on various spaces within YouTube, such as the homepage, "Up Next" on the watch page, in search results, and even in subscription feeds. Impressions are important because they give creators an indication of how many people are seeing their videos in the search results. A high number of impressions show creators that YouTube thinks their content is useful, whereas a low impression metric indicates that a creator needs to change or modify their YouTube SEO and video optimization strategies in order to attract more impressions. Impressions click-through rate measures how often viewers watched a video after seeing a registered impression on YouTube. It likely represents a subset of a channels total views, since not all impressions are counted in this metric, such as those on external websites or end screens.