A keyword is a predefined word or a reserved word for a purpose. In C language there are totally 32 keywords. All the key words and their description is mentioned in the following tabular format. Please check the following table for a better understanding of each of the keyword.
Keyword
|
Description
|
auto
|
Default Storage Class
|
break
|
Command that exits the current flow unconditionally in for, while,
switch, do…while
|
case
|
Command used within switch statement
|
char
|
C data type used to carry characters.
|
const
|
Data modifier that prevents a variable from being changed.
|
continue
|
Command that resets loops to next iteration.
|
default
|
Command used within the switch statement to catch any instances which
doesn’t go under any case.
|
do
|
Looping command used in do…while loop
|
double
|
Data type that holds double precision floating-point variables.
|
else
|
Alternative path if failed in if condition.
|
enum
|
Data type that allows variables to be declared that accepts only
certain values.
|
extern
|
Data modifier indicating that a variable will be declared in another
area of the program.
|
float
|
Floating-point data type
|
for
|
Looping command
|
goto
|
Jump to predefined label.
|
if
|
Condition statement
|
int
|
Integer data type
|
long
|
Larger Inetegr values data type
|
register
|
Storage modifier to make storage in registers.
|
return
|
For returning a value to calling function
|
short
|
Used to store small integer values.
|
signed
|
To signify that variable can have both positive and negative values.
|
sizeof
|
Returns the size in bytes.
|
static
|
To signify that compiler should retain its value.
|
struct
|
To define structures
|
switch
|
To choose between cases using a single variable
|
typedef
|
To create new names for existing variable and function types.
|
union
|
To create unions
|
unsigned
|
To signify that it takes only positive values.
|
void
|
To state that it is nothing or returning nothing.
|
volatile
|
Signifies that a variable can be changed.
|
while
|
Looping Statement
|
All these keywords are reserved words in C. These words can't be used for other purposes in C. These keywords can't be used as variable names in C.
Along with these keywords, there is another word which doesn't come under the keywords but can't be used as a variable in C i.e., asm.
ASM in C:
asm in a word which helps us to write inline Assembly code. We can write the assembly code in between a C program by just writing inside of the asm.
For example,
asm("movl %ebx, %eax");
This statement moves the contents of the register ebx into the register eax.
Also we can write the above statement as
_asm_("assembly code");
Thus we can embed assembly code into our C program.
