All devices on the World Wide Web are identified by a special number called an IP address, for instance 123.123.123.123. 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. Considering that there are far more websites and devices than there are IP addresses, all of the shared web hosting servers have a number of websites under the very same IP, while with a dedicated server you will have a dedicated IP too. Even in the first case though, you're able to obtain a dedicated IP for your sites and host them on a shared server. One advantage would be that you'll enjoy superior search engine positions as a dedicated IP generally means a quicker loading website. Furthermore, you need such an IP in case you intend to purchase an SSL certificate for your site and shield the information that your visitors submit on it.