Include sub-paths in redirect?
When this option is set to No, any sub-directory or filename under the source URL path will not be appended to the redirect. For instance, redirecting from /google to http://google.com means that accessing http://example.com/something will lead you directly to http://google.com, without including the /something part.

On the other hand, if you choose Yes, and a browser accesses http://example.com/something, the resulting URL would be http://google.com/something. However, this inclusion requires the placement of the special code $1 in the destination URL, representing the sub-path or filename that follows the source URL path.