C Language | Keywords

C Keywords – Reserved Words

In C, we have 32 keywords, which have their predefined meaning and cannot be used as a variable name. These words are also known as “reserved words”. It is good practice to avoid using these keywords as variable names. These are –

List of Keywords in C 

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  

Basics usage of these keywords –

if, else, switch, case, default – Used for decision control programming structure.

break – Used with any loop OR switch case.

int, float, char, double, long – These are the data types and used during variable declaration.

for, while, do – types of loop structures in C.

void – One of the return type.

goto – Used for redirecting the flow of execution.

auto, signed, const, extern, register, unsigned – defines a variable.

return – This keyword is used for returning a value.

continue – It is generally used with for, while and dowhile loops, when compiler encounters this statement it performs the next iteration of the loop, skipping rest of the statements of current iteration.

enum – Set of constants.

sizeof – It is used to know the size.

struct, typedef – Both of these keywords used in structures (Grouping of data types in a single record).

union – It is a collection of variables, which shares the same memory location and memory storage.