Most languages only tend to allow them in string literals, or identifiers. Java is fairly unique in that it has a pre-processor that replaces those throughout t

Most languages only tend to allow them in string literals, or identifiers. Java is fairly unique in that it has a pre-processor that replaces those throughout the source code before actually compiling. Which means that a lot of benign-looking source code can have fairly surprising behaviour, such as exhibited in the polyglot where //\u000Afoo actually cancels the line comment.