All devices on the World Wide Web are recognized by a specific number called an IP address, for example 220.127.116.11. When you have a site, the domain that you enter to access it is for your convenience, yet the server where the site files are still has an IP. Due to the fact that there are far more websites and devices than there're IP addresses, all shared website hosting servers have a number of sites under an identical IP, whereas with a dedicated server you will have a dedicated IP as well. Even in the first case though, you can acquire a dedicated IP for your websites and host them on a shared server. One advantage would be that you will have better search engine rankings since a dedicated IP usually means a quicker loading site. Also, you need such an IP if you want to purchase an SSL certificate for your site and protect the information that visitors submit on it.