Because you have to: any executable statement in C must belong to one function or another; there mustn't be executable statements outside of functions.and it also reduces the length of the program
compound c language is complicated where we need to use many nested functions and loops
Impossibility.
The c language does not have template functions. That is a c++ thing.
C++ built-in functions are those functions that are provided for you as part of the language itself, and includes all of the C standard library functions (all of which were inherited from C) and is expanded upon by the C++ standard template library. C++ implementors may provide additional functions that are platform-specific, however these are not considered built-in functions becuase C++ is a cross-platform language. These are best described as 3rd party functions. The functions you yourself write are known as user-defined functions.
An identifier is the names given for labels, functions and variables in the c language.
constants, MAX_(function), etc.
Library functions
I do use am a programmer, because C-language.
No, because C does not support the concept of template functions. Template functions only exist in C++, never in C.
Header File in C/C++ are the files which contains the definition of the pre-defined functions, data-types & constants, etc. By adding the header file you reduce your job of defining the same functions which are defined earlier by someone else & you can use those functions/data-types easily.
Programming languages cannot be 'portable', but programs written in C might be portable, if they follow the strictest standards and do not use platform-specific features or functions.
You can't. HTML is a markup language. C is a programming language. You can make C generate HTML, but C isn't anything like HTML in the way it functions.