Oscar the Grouch Day is celebrated on June 1, marking the birthday of the fictional character Oscar the Grouch from the television series "Sesame Street." Oscar is depicted as a green character who lives in a trash can and expresses a dislike for celebrations, believing that the best part of birthdays is the year-long gap between them. The character was introduced in the show, which began airing in 1969, and his design evolved from a spiky magenta monster to a green figure after a fictional vacation that left him moldy. Oscar's personality is characterized by grumpiness, as highlighted by his iconic line, "Don't bang on my can! Go away." The day is an opportunity for fans to appreciate the character and the show's impact on children's television, often celebrated with themed activities or discussions about Oscar's unique traits and cultural significance.