I have seen the secret on Apache's rewrite guide regarding how to redirect non-world wide web demands to world wide web demands:

RewriteCond %   !^www.example.com [NC]

RewriteCond %   !^$

RewriteRule ^/(.*)         http://world wide web.example.com/$1 [L,R]

Which redirects all demands for instance.com to world wide web.example.com.

But how do you add for the reason that I would like demands from example1.com, world wide web.example1.com, example2.com, world wide web.example2.com, etc. to redirect to world wide web.example.com?

EDIT:

Here's the answer:

RewriteEngine on

RewriteCond % !^www.example.com [NC]

RewriteCond % !^$

RewriteRule ^/?(.*) http://world wide web.example.com/$1 [L,R,NE]

Slightly different RewriteRule and added 'RewriteEngine on'

But how do you add for the reason that I would like demands from example1.com, world wide web.example1.com, example2.com, world wide web.example2.com, etc. to redirect to world wide web.example.com?

You've already done that. Your rewrite rule states "if HTTP_HOST is not world wide web.example.com (and is not blank), redirect to world wide web.example.com".

As lengthy as the server is to establish to suggest another domain names in the same directory you are hosting world wide web.example.com from, you are ready.