Yes, and it's quite easy to do. Routers and modems we normal users use to connect to Internet normally use IP addresses in series 10.0.X.X, 172.16.X.X or 192.168.X.X. So, for instance your router's IP i.e. your DHCP server address is most probably 192.168.1.1. If you now let's say visited me, you could not join my network keeping your old IP because my DHCP server address is 192.168.2
If you didn't have a static IP to connect to my router, it (DHCP server) would then assign you an IP address from my address pool, which I have limited to 99 addresses as this image shows:
If you visited me often, we could for instance agree that you can always use 192.168.2.15 when here. You can set a static IP for every network you normally use as for instance I have set this laptop to have these two addresses (WiFi & LAN) when home here in Leipzig:
When in our other home, other side of Germany, I have two other static IP's. I also have a static IP to use in my favourite pub; the owner is a friend and let's me use his fast gigabit office network so I don't have to use the slow public WLAN when sitting there with my laptop.
To create a connection for every network you regularly visit, open the Network and Sharing Center
, click Connect to a network
, and follow the instructions.
Go then to each connection's properties and set DHCP, DNS and IP info manually. Result is this: