All devices on the Internet are identified by a specific number called an IP address, such as 18.104.22.168. In case you have a website, the domain name that you enter to be able to load it is for your convenience, yet the server where the website files are still has an IP address. Considering that there are many more websites and devices than there are IP addresses, all of the shared website hosting servers have a number of sites under the very same IP, whereas using a dedicated server you'll have a dedicated IP too. Even in the first case though, you are able to get a dedicated IP for your sites and host them on a shared server. One benefit would be that you may get superior search engine rankings as a dedicated IP generally means a quicker loading site. What's more, you need such an IP in case you want to get an SSL certificate for your site and secure the info that your visitors submit on it.