localhost vs real ip address

Question

What is the difference between the localhost and the real ip address?

If I access an application by using http://localhost:8080/index.html and ht

Answer 1

Additionally to the other answers you can run into mysterious problems with using localhost.

One example: IE on Windows makes a shortcut if you enter http://localhost into the URL bar. That becomes a problem when you are developing a web application and have a local proxy installed (such as Fiddler) to peek into messages passing between the client webpage and the server both running locally - the message will not be captured because it will not pass through the proxy in this case. Which makes it a bit inconvenient to find IE-only bugs in your application... ;-)