videos. Parodies, spoofs and spin-offs often indicate a popular video, with long-popular video view counts given with original video view counts as well as additional view counts given for the parodies. Longevity indicates if a video has remained part of the Zeitgeist. Reasons for popularity Due to their societal impact and marketability, viral videos attract attention in both advertising and academia, which try to account for the reason viral videos are spread and what will make a video go viral. Several theories exist. A viral video's longevity often relies on a hook which draws the audience to watch it. The hook is able to become a part of the viral video culture after being shown repeatedly. The hooks, or key signifiers, are not able to be predicted before the videos become viral. The early view pattern of a viral video can be used to forecast its peak day in future. Notable examples include "All your base are belong to us", based on the poorly translated video game Zero Wing, which was first distributed in 2000 as a GIF animation and became popular for the grammatically incorrect hook of its title, and Don Hertzfeldt's 2000 Academy Awards Best Animated Short Film nomination "Rejected" with the quotable hooks "I am a banana" and "My spoon is too big!" Another early video was the Flash animation "The End of the World", created by Jason Windsor and uploaded to Albino Blacksheep in 2003, with quotable hooks such as "but I'm le tired" and "WTF, mates?" Rosanna Guadagno, a social psychologist at the University of Texas at Dallas, found in a study that people preferred to share a funny video rather than one of a man treating his own spider bite, and overall they were more likely to share any video that evoked an intense emotional response. Two professors at the Wharton School at the University of Pennsylvania also found that uplifting stories were more likely to be shared on the New York Times' web site than disheartening ones. Others postulate that sharing is driven by ego in order to build up an online persona for oneself. Chartbeat, a company that measures online traffic, compiled data comparing the amount of time spent reading an article and the number of times it was shared and found that people often post articles on Twitter they haven't even read. Categories by subject Band and music promotion Many independent