What does the mask mean?

Among most superheroes a common trait is that they have a mask (besides X men, Hulk, Thor, Wonder Woman, Dr. Strange and Superman) although that's a lot of exceptions we will address those later. But why do superheroes wear masks? Is it just a form of disguise? I don't think so. Let's discuss a couple of heroes and their reasons for wearing the masks. As a child dressing up for Halloween my least favorite part was the mask because it was as sweaty as all get out so it worth it? The main use for the mask or the outfit in general as Ra's Al Ghul put it in Batman Begins is (to paraphrase) that it you have to be more than a man. A symbol. To be honest more that one person can be taking that persona of Batman. There might even be a Batman organization of people who are Batman all over the world. Although this is only in the comics, there is a real super hero organization who wear costumes and do work for the good of humanity. Not for hiding identity but as a symbol. What do you think the mask is for? Comment below to state your thoughts.