Using any protocol to transfer files on web.For example when a client is sending a request to www.google.com, the requested page will be given to the client, in this case he/she did not use a port numbr wen writing. So my question is that why we do not specify a port number when sending request?
Actually the port can be specified.
However, there are some standard ports 80 => HTTP 443 => HTTPS
When you don't enter anything into your browser (eg. http://www.google.com) your browser is really requesting (http://www.google.com:80) - the port number is just implied. Likewise, when you view https://www.google.com your browser is really making a request to https://www.google.com:443