Localhost: is telling the server to loop back on itself, so instead of sending a HTTP request to a forgien server to send it to a local server,
8080:, refers to the port number,
/url/hello/ refers to the directory structure within the local server
so yes if you are migrating your code from local to live then
http://localhost:8080/url/hello
will become
http://www.mywebsite.ie/url/hello