What is an identifier in compiler design?

In compiler design, an identifier is a name used to identify a variable, function, class, or any other user-defined item in a program. Identifiers are crucial for representing data and accessing it during compilation and execution. They must adhere to specific naming conventions, such as starting with a letter or underscore and being followed by alphanumeric characters or underscores, ensuring they are unique within their scope to avoid conflicts. Proper handling of identifiers is essential for symbol tables and scope management in the compilation process.