How to Perform a Query Replace
To replace a character string everywhere that it occurs within the
current buffer, there is two ways to do it
M-x replace-string
will ask you for the string you want to replace and what you want to
replace it with. Once you provide these, it will make the change
globally within the buffer.
M-%
will also prompt you for the string to search for and the string to
replace it. It differs from M-x replace-string in
that it asks for verification before making each change.
In order to enter control characters in either of the above, they will
have to be preceded by C-q. For example, ^J is typed
as C-q C-j.