Superman Classic Logo Collection
What's the most recognized superhero symbol in the world? If your a Batman fan most likely you would say the iconic bat logo. But many Superman fans would argue that Superman’s red-and-yellow S-shield is an iconic symbol with its diamond shape and "S" are immediately recognizable.
One story (myth?) is that in 1934 the creators of Superman, Jerry Siegel and Joe Shuster, wanted to put something on his chest. They chose the first letter S since it was the first letter of Superman’s name. Although some say that they jokingly said that they choose the "S" because it's the first letter of their names: Siegel and Shuster. Either explanation sounds valid.
The tradition of wearing a representative symbol on the chest of many subsequent superheroes, including Batman, Green Lantern, the Flash, Wonder Woman, Hawkman, and many others was started with Superman.
The history of the design of Superman's S symbol and the explanations from various comic book story lines as to its meaning is fascinating.
The Superman Classic Logo Collection shows Superman's symbol in its most classic iteration that first appeared in 1977 and is still relevant today. The collection's design shows black outlined red (pentagonal) 5 sided shield with a large red S centrally anchored against a gold/ yellow backgtround, printed on royal blue fabric.
Wikipedia has an informative page about the evolution of the symbol's design called: Superman Logo.