The Sesame Street YouTube Hack refers to a notorious 2011 incident where the official Sesame Street YouTube channel was compromised and flooded with explicit content. For approximately 20 minutes, the beloved children's brand became the center of a massive internet shockwave, leading to a wave of memes about childhood trauma and the unexpected vulnerability of major platforms. Today, the meme is used to depict situations where something wholesome is suddenly and jarringly subverted by something inappropriate or chaotic. It remains a definitive piece of internet lore, representing the wild and unpredictable nature of early 2010s web security.