For as long as there have been heroes, there have been costumes and uniforms to strike fear into the villains and give hope to the people. The first hero to wear such a costume was Don Diego De La Vega, better known as
. Which, according to Frank Miller's "
The Dark Knight Strikes Again
", inspired Bruce Wayne to use the guise of a Dark figure to instill fear into Criminals.
Some costumes, however, serve no purpose in concealing one's identity, but have a more physical purposes in wearing, like Tony Stark's
Suit, Shining Knight/Black Knight Armors or Doctor Doom's Armor. Likewise, some costumes are merely used to withstand the wear and tear of battle, like Superman's Costume, which, according to the Golden Age version of Superman, was forged from the blankets and clothing baby Kal-EL brought in his rocket ship from Krypton... And Others, just enhance a Hero / Villains Powers, such as Spider-man's Web-Shooters and Batman's utility belt and armor.
Uniforms have been used for millenia by the military to identify their soldiers and recently to identify the police on the streets, they are used in folklore to stereotype creatures, like vamires and witches. Costumes are a symbol of theatricality, which goes above reality and normality, they show the world that the wearer is willing to stand out from the crowd.
style for each new time period. When a character experiences a dramatic (or less dramatic) change, they often change their appearances as well as their attitudes. But with new clothes, their identities/personalities stay the same until the character assumes a new identity for themselves.