All devices on the World Wide Web are identified by a unique number called an IP address, for example 123.123.123.123. If you have a website, the domain that you type to be able to open it is to save you time, yet the server where the site files are still has an IP. Considering that there are a lot more sites and devices than there're IP addresses, all shared website hosting servers have a number of websites under the very same IP, whereas using a dedicated server you'll have a dedicated IP too. Even in the first case though, you'll be able to obtain a dedicated IP for your websites and host them on a shared server. One benefit would be that you will have superior search engine positions since a dedicated IP often means a quicker loading site. Also, you need such an IP if you plan to buy an SSL certificate for your site and secure the info that your visitors submit on it.