For example: http://www.anyurl.com/?query=1 - valid URL http://www.anyurl.com?query=1 - invalid URL (missing slash after `.com` and before `query=1`) I'm not sure if last url is valid according to RFC: https://tools.ietf.org/html/rfc3986#page-16 https://tools.ietf.org/html/rfc3986#page-22