Why-Would-You-Use-a-Static-IP-Address-
Another way to think of a static IP address is to think of something like an email address, or a physical home address. These addresses don't ever change - they're static - and it makes contacting or finding someone very easy. Similarly, a static IP address is useful if you host a website from home, have a file server in your network, are using networked printers, are forwarding ports to a specific device, are running a print server, or if you use a remote access program. Because a static IP address never changes, other devices always know exactly how to contact a device that uses one. For example, say you set up a static IP address for one of the computers in your home network. Once the computer has a specific address tied to it, you can set up your router to always forward certain inbound requests directly to that computer, such as FTP requests if the computer shares files over FTP. Not using a static IP address (using a dynamic IP that does change) would become a hassle if you're hosting a website, for example, because with every new IP address that the computer gets, you'd have to change the router settings to forward requests to that new address. Neglecting to do this would mean nobody could get to your website because your router has no idea which device in your network is the one that's serving the website. Another example of a static IP address at work is with DNS servers. DNS servers use static IP addresses so that your device always knows how to connect to them. If they changed often, you'd have to regularly reconfigure those DNS servers on your router or computer to keep using the internet like you're used to. Static IP addresses are also useful for when the device's domain name is inaccessible. Computers that connect to a file server in a workplace's network, for instance, could be set up to always connect to the server using the server's static IP instead of its hostname. Even if the DNS server is malfunctioning, the computers could still access the file server because they'd be communicating with it directly through the IP address. With remote access applications like Windows Remote Desktop, using a static IP address means you can always access that computer with the same address. Using an IP address that changes will, again, require you to always know what it changes to so that you can use that new address for the remote connection.
