Symbol is one of those Ruby concept that is hard to grok for C# programmers. It's a name for object (what ?)

Read this good explanation about what a symbol is (because Ruby help file is useless on this topic)

"You can’t ask for the size of a symbol. You can’t ask for a substring of the symbol. You can’t do anything that you can do with strings on Symbols except (1) convert it to an integer (using to_i) and (2) convert it to a symbol (using to_sym). If a symbol is not a duck-type for a String, it hardly seems reasonable to call Symbols any kind of String, even immutable ones." (onestepback)