The 'Hold the Fuck Up' meme typically features an edited version of the Fallout mascot, Vault Boy, with a concerned and suspicious expression, though it has evolved to include various characters like Tom Cat. It gained massive popularity across Reddit and Twitter as a high-tier reaction image used to signal that something in a previous statement or image is deeply wrong or needs immediate clarification. Often used in a story-telling format, the top text describes a seemingly innocent scenario that quickly takes a dark or absurd turn, prompting the 'hold up' response. It remains a staple of internet humor for highlighting cognitive dissonance and those specific 'wait, what?' moments in social media conversations.