Jackie Robinson Day is observed annually on April 15, celebrating the legacy of Jackie Robinson, the first African American to play in Major League Baseball in the modern era. This day commemorates his major league debut on April 15, 1947, which marked the end of approximately eight decades of racial segregation in professional baseball. The event began in 2004 and has since become a tradition across Major League Baseball, where players, coaches, and umpires wear the number 42 on their jerseys to honor Robinson. Jackie Robinson was born in 1919 and made significant contributions to the sport, culminating in his induction into the Baseball Hall of Fame in 1962. Celebrations take place at ballparks throughout the United States, emphasizing Robinson's impact on baseball and civil rights.