What is the use of a semicolon (;) at the end of every program statement?

Question

while(i<10);
{
  i++;
  printf("%d,\n", i);
}

Loop does not run for 10 iterations, what is the error?

Answer 1

The semicolon is a statement terminator in C to help the parser figure out where the statement ends since, by default, statements in C (and C++ and Java) can have any number of lines.if your question was why the C folks chose the semicolon character specifically, I'd guess it's probably because C came out around the time ALGOL, PASCAL and PL/I and they all used semicolons as either separators or terminators.
In C a statement does not necessarily mean action(like increment and decrement and so on) statement,even assigning and declaring a variable will be considered as statements.Take a look at this code

for(i=0;i<10;i++)
{
printf("%d",i);
}

see these points:
1.There is no semicolon after for,because if that's the case the body of loop is not at all executed
but a delay takes place,as continuous increment and condition check takes place till the condition fails.
2.i=0 i.e. assign i with zero,is a statement and hence end with ;
3.i<10 a relational statement so end with ;
4.i++ although a statement don't end with semicolon as it is against the syntax of for loop.
5.printf is a statement and hence end with ;
Now that's the use of ; in C.

Answer 2

The semicolon is a statement terminator in C to help the parser figure out where the statement ends since, by default, statements in C (and C++ and Java) can have any number of lines. 

Note that there is a subtle distinction between semicolons as terminators (as they are used in C) and semicolons as separators (as they are used in Pascal). This latter use is on the decline and if you are interested in reading more, here are a couple of references:

Answer 3

It has to do with the parsing process and compilation of the code. A semicolon acts as a delimiter, so that the compiler knows where each statement ends, and can proceed to divide the statement into smaller elements for syntax checking.