ipconfig by itself will provide the IP address of the currently-in-use network adapter.
ipconfig /all shows all settings on all configured network adapters, including the DNS server IPs and suffixes applied.
ipconfig /release will release the binding of the network adapter.
ipconfig /renew will renew the connections.
ipconfig /flushdns will flush the DNS cache on the machine so it pulls new IPs from the DNS server instead of using local cache.
ipconfig ? will give you a list of the other possible commands with a short explanation and all possible switches.
