All devices on the World Wide Web are recognized by a specific number called an IP address, for example 126.96.36.199. When you have a website, the domain that you enter to access it is to save you time, yet the server where the site files are still has an IP address. Since there are far more websites and devices than there're IPs, all the shared web hosting servers have a number of websites under the very same IP, while using a dedicated server you'll have a dedicated IP too. Even in the first case though, you're able to obtain a dedicated IP for your websites and host them on a shared server. An advantage would be that you'll have far better search engine positions because a dedicated IP often means a faster loading site. What is more, you need such an IP in case you intend to obtain an SSL certificate for your site and protect the data that visitors submit on it.