Types: _Bool, _Complex, and _Imaginary

 

we should mention three other types in the language: _Bool,
for working with Boolean (that is, 0 or 1) values, and _Complex and _Imaginary, for working with complex and imaginary numbers, respectively

Objective-C programmers tend to use the BOOL data type instead of _Bool for working with Boolean values in their programs.This “data type” is actually not a data type unto itself, but is another name for the char data type.This is done with the language’s special
typedef keyword