What term is used for reserved keywords in C++ that cannot be used as variable names?

The term used for reserved keywords in C++ that cannot be used as variable names is "reserved words." Reserved words are specific words that are predefined in the C++ language with special meanings, and they serve as the foundational building blocks for writing code. Because these words are integral to the syntax and structure of the language, they cannot be repurposed as identifiers for variables, functions, or other user-defined elements.

For example, words such as "int," "class," "return," and "if" are reserved words in C++. Attempting to use them as variable names would result in a compilation error because the compiler recognizes them as part of the language's syntax.

Keywords, while often used interchangeably with reserved words, generally refer to the same concept but might not encompass the full scope of terms reserved in the language. Identifiers refer to names created by programmers for variables, functions, etc., while functions pertain to blocks of code designed to perform a specific task and are not directly related to the concept of reserved words.