Skip to content



Before you can do anything in any language, you must know how to name an identifier. An identifier
is used for any variable, function, data definition, etc. In the C programming language, an identifier is
a combination of alphanumeric characters, the first being a letter of the alphabet or an underline, and
the remaining being any letter of the alphabet, any numeric digit, or the underline.


There are 32 words defined as keywords in C. These have predefined uses and cannot be used for any
other purpose in a C program. They are used by the compiler as an aid to compiling the program.
They are always written in lower case. A complete list follows;
auto           double      int             struct
break        else          long           switch
case          enum        register     typedef
char          extern      return        union
const         float         short         unsigned
continue    for           signed        void
default      goto         sizeof         volatile
do              if              static         while

#include <stdio.h>
int main()
int i;
for (i = 0 ; i <8 ; i = i + 1)
printf(“First example program.n”);
return 0;