Fixed IP which is also known as Static (or) Dedicated IP. To get Fixed IP,
you need to contact the Network service provider. Normally Static IP
never gets changed of its IP address whenever you reset (or) unplug your
modem. Fixed IP can be changed only by requesting the Service
provider. To check whether your have a Fixed IP address, visit the site
IP-details.com .

This is your unique number that shows your computer's identity every time you go on the internet. This gives you a better connection, easier remote access and better internet use generally.
It's easy to get one, in fact some providers offer them free as part of the package. You could start by checking what your current provider is offering. If it is not free it will be available at a small charge - £5 or so a month with some providers (more if you get it month by month, less if you buy in bulk), but you can get it cheaper if you look around. There may also be disadvantages to do with security though, so you should look into these as well before you decide to get a static address.
If you do decide to go with this, you can set it up yourself or you can contact your provider and ask for help.