Stuff function: - This function is used to replace string from the given start position, passed as 2nd argument with string passed as last argument. In Stuff function, 3rd argument defines the number of characters which are going to be replaced.Syntax:-STUFF ( character_expression , start , length , replaceWith_expression )For example:-Select Stuff ('Software', 3, 3, 'abc') Replace Function :- Replace function is used to replace all occurrence of a specified with the string passed as last argument.Syntax :- REPLACE ( string_expression , string_pattern , string_replacement )For example:- Select Replace ('Software','ftw' , 'abc')