All devices on the World Wide Web are identified by a specific number called an IP address, such as 123.123.123.123. If you have a site, the domain name that you type in order to open it is to save you time, but the server where the website files are still has an IP address. Because there are a lot more websites and devices than there are IPs, all of the shared hosting servers have a number of sites under an identical IP, whereas using 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 sites and host them on a shared server. One advantage would be that you will have better search engine positions since a dedicated IP often means a quicker loading site. What is more, you need such an IP when you plan to get an SSL certificate for your website and protect the data that visitors submit on it.