All devices on the Internet are identified by a special number called an IP address, for instance 123.123.123.123. If you have a website, the domain that you enter to open it is to save you time, yet the server where your website files are still has an IP. Since there're many more websites and devices than there're IPs, all of the shared website hosting servers have a number of websites under an identical IP, whereas using a dedicated server you'll be given 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. One benefit would be that you may enjoy superior search engine positions since a dedicated IP generally means a faster loading site. In addition, you need such an IP when you intend to purchase an SSL certificate for your site and protect the information that visitors submit on it.