I think you came to this post sine you or someone already had installed httpauth on your websites/server. Here is a guide on how to add http auth on a Apache server. But times removing httpauth also important, that could be your application need to communicate with 3rd party system or you need to expose the website to cretain types of crawlers or bots, that could be anything.
Removing httpauth is simple. First if you don't have a .htaccess file on your document root, start adding it (I prefer .htaccess way, this need allow overrides permissions). Then add following lines to the .htaccess to remove httpauh on that folder.
Allow from all