GLFW is a C library, not a C++ one, and an old one at that, and so the reason is that a long time ago, there was no bool in C. Every library would make their own true and false bc it's handy to have.
Nowadays, the type _Bool
has been added to C, and C++ has built-in bool
, but you can still see the legacy of no boolean in C as to use the type name "bool" as well as the key words "true" and "false" for 1 and 0, you have to include "stdbool.h," as well as in custom types in these old GL-adjacent libraries.