point, just as a forward search finds matches that begin after it.
The characters @kbd{C-y} and @kbd{C-w} can be used in incremental
-search to grab text from the buffer into the search string. This makes
-it convenient to search for another occurrence of text at point.
-@kbd{C-w} copies the word after point as part of the search string,
-advancing point over that word. Another @kbd{C-s} to repeat the search
-will then search for a string including that word. @kbd{C-y} is similar
-to @kbd{C-w} but copies all the rest of the current line into the search
-string. Both @kbd{C-y} and @kbd{C-w} convert the text they copy to
-lower case if the search is currently not case-sensitive; this is so the
-search remains case-insensitive.
+search to grab text from the buffer into the search string. This
+makes it convenient to search for another occurrence of text at point.
+@kbd{C-w} copies the character or word after point as part of the
+search string, advancing point over it. (The decision, whether to
+copy a character or a word, is heuristic.) Another @kbd{C-s} to
+repeat the search will then search for a string including that
+character or word.
+
+ @kbd{C-y} is similar to @kbd{C-w} but copies all the rest of the
+current line into the search string. Both @kbd{C-y} and @kbd{C-w}
+convert the text they copy to lower case if the search is currently
+not case-sensitive; this is so the search remains case-insensitive.
The character @kbd{M-y} copies text from the kill ring into the search
string. It uses the same text that @kbd{C-y} as a command would yank.
A numeric argument restricts replacement to matches that are surrounded
by word boundaries. The argument's value doesn't matter.
+ What if you want to exchange @samp{x} and @samp{y}: replace every @samp{x} with a @samp{y} and vice versa? You can do it this way:
+
+@example
+M-x query-replace @key{RET} x @key{RET} @@TEMP@@ @key{RET}
+M-x query-replace @key{RET} y @key{RET} x @key{RET}
+M-x query-replace @key{RET} @@TEMP@@ @key{RET} y @key{RET}
+@end example
+
+@noindent
+This works provided the string @samp{@@TEMP@@} does not appear
+in your text.
+
@node Regexp Replace, Replacement and Case, Unconditional Replace, Replace
@subsection Regexp Replacement