A peanut butter and jelly sandwich (PB&J) is a sandwich that consists of peanut butter and fruit preserves spread on sandwich bread. It is known for its popularity among children in the United States and is considered a comfort food. The earliest recorded mention of a peanut butter and jelly sandwich appeared in 1901, suggesting it as a tea sandwich. It was popularized in the United States after mass-production made peanut butter accessible. Its nutritional value and long shelf-life made it a common meal for the poor during the Great Depression, and it was eaten by American soldiers during World War II. The sandwich was ingrained in popular culture by the 1950s and 1960s. Concern about peanut allergies has eroded its prominence as a school meal in the 21st century.