What's a character?

What this C++ character-handling interview question tests

This is an easy C++ question that probes whether you understand how the language defines and handles character types, and how modern compiler standards affect what code is valid. It's less about exotic edge cases and more about foundational language semantics.

Questions like this reward clarity on the distinction between different character types (char, signed char, unsigned char, wchar_t, and the newer char8_t, char16_t, char32_t in C++11 and beyond), how they interact with literals and strings, and what the compiler expects. A solid answer demonstrates that you've read the standard or worked through enough real code to spot subtle type mismatches that silently compile in some modes but fail in others.

• Character literal types and their implicit conversions
• Signedness of plain char
• Modern C++ standard versions and their type system
• Compiler warnings vs. errors in different contexts