Lunch boxes have changed in design and shape over the years, but the basic idea is the same. Along with space inside for a cold drink, sandwich and (the dreaded) piece of fruit, the cover is devoted to a favorite cartoon, character, TV show or movie.
That's why Justin Bieber and Darth Vader and Japanese cartoon characters are grace the frong of lunch boxes on the shelves of stores everywhere.
Back in the 1960s and '70s, the lunch boxes were aluminum. In the '80s, they gave way to plastic. Vintage lunch boxes now are highly collectible. They are displayed as collections in people's homes, and sometimes they get their own art gallery shows.