All devices on the World Wide Web are recognized by a specific number called an IP address, for example 123.123.123.123. If you have a website, the domain name that you type to be able to open it is for your convenience, yet the server where your site files are still has an IP address. Since there're far more sites and devices than there are IP addresses, all shared hosting servers have a number of websites under the same IP, while with a dedicated server you will have a dedicated IP too. Even in the first case though, you will be able to obtain a dedicated IP for your sites and host them on a shared server. One benefit would be that you may enjoy far better search engine rankings since a dedicated IP generally means a faster loading site. In addition, you need such an IP when you want to buy an SSL certificate for your website and protect the data that visitors submit on it.