(assuming windows)
At your machine at a command prompt type: ipconfig to get your ip...
specific instructions:
click windows orb,
then type cmd in text area
type ipconfig and press enter
line reading IPv4 Address will have an IP address x.x.x.x... use that IP address in place of localhost.
Assuming others on network are within the same subnet and not have vlans and what not, it should work
a URL uses something called DNS or a hosts file to lookup that name and translate that common name to an IP address, by specifing the IP address and port, you avoid the need for the DNS, assuming the IP address is "Routable" for the users needed to access it.
Here's an example: Type http: //74.125.225.176 in a browser and you get google search! There's alot more to this really, but this is just the basic workings.