Well, in simple words, they are the function that you use by #including some libraries like <stdio.h> or <stdlib.h>. By including these libraries you got access to many functions that you can use to help you make your program. Not only functions can be stored in a library, but the majority of these libraries only got functions in them. These libraries got some differences between them and that depends on what do we want and how do we create them.
To understand GCC and all the process of the compilation behind the scene it’s important to first talk about C language (just the basic, don’t worry), the gcc and what happen after we compile a C file.
C is a programming language that was first developed in 1972 by Dennis Ritchie at AT&T Bell Labs. It was called C because there was already a B language and, fun fact, B led the development of C.
C is a high-level language but since some of the most popular high-level languages created right now are better in many ways than C, some…