All devices on the Internet are identified by a specific number called an IP address, for example 123.123.123.123. If you have a site, the domain that you enter to be able to open it is to save you time, yet the server where the website files are still has an IP. Due to the fact that there are a lot more sites and devices than there are IP addresses, all of the shared hosting servers have a number of sites under the same IP, while when you use a dedicated server you'll get a dedicated IP as well. Even in the first case though, you are able to get a dedicated IP for your websites and host them on a shared server. One benefit would be that you'll enjoy better search engine rankings since a dedicated IP usually means a quicker loading site. Last but not least, you need such an IP when you would like to get an SSL certificate for your site and shield the information that visitors submit on it.