Doubt in xmlDocDumpFormatMemoryEnc

Hi All,
 
I am calling the function xmlDocDumpFormatMemoryEnc() to construct xmlDocPtr
to xmlChar.
When i used this function, the left characters are converted to right
characters. Can you please let me know what is the reason to convert like
this.
 
 
& - &
> - <
< - &gt;
" - &quot
' - &#39;
\r - &#13;
 
Thanks and Regards,
Bharath.
 
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