A Comparative Analysis of Information Hiding Techniques for Copyright Protection of Text Documents

Table 5

Special spaces based 3-bits group coding [42].

Number	Name	Reference type	Code type	Code inserted in HTML	Bits encode
	(Normal) space	Normal space	ASCII	Typed space; (with 20 h inserted)	000
	(Normal) space	Numeric character reference	Unicode	 	001
	(Normal) space	Numeric character reference	Unicode	2	010
	(Normal) space	Numeric character reference	Unicode	&#x32	011
	Nonbreak space	Numeric character reference	Unicode	 	100
	Nonbreak space	Numeric character reference	Unicode	 	101
	Nonbreak space	Numeric character reference	Unicode	&#160	110
	Nonbreak space	Character entity reference	HTML	 	111
	Nonbreak space	Character entity reference	HTML	&nbsp	Unused