The 'Smiling and Unsmiling Seong Gi-hun' meme features two contrasting images of the protagonist from the Netflix hit series Squid Game. The first image captures his optimistic, wide-eyed profile photo as Player 456 at the start of the competition, while the second shows his hardened, traumatized expression from the end of the series. This template is primarily used to represent the 'How it started vs. How it's going' trope, highlighting a drastic decline in mood or a harsh reality check. It resonates with audiences by humorously depicting how life, work, or specific events can quickly drain one's initial enthusiasm.