Back slash character constan

c includes some back slash character constant.
so you may easily enter these special character as constant.
They are also reffered as escape sequence.

#include
int main(void)
{

printf("\n\t This is a test.");
return 0;
}

code            meaning

\b                Back space
\f                 form used
\n                new line
\r                 carriage return
\t                 horizantal tab
\"                Double quote
\'                 Single quote
\\                 Back slash
\v                vertical tab
\a                Alert
\?                Question mark
\N               octal constant
\xN             Hexadecimal constant