All devices on the Internet are identified by a specific number called an IP address, such as 188.8.131.52. If you have a site, the domain name that you type to load it is to save you time, yet the server where your website files are still has an IP. Because there're far more sites and devices than there are IP addresses, all of the shared website hosting servers have a number of websites under an identical IP, whereas with a dedicated server you'll be given a dedicated IP as well. Even in the first case though, you'll be able to get a dedicated IP for your websites and host them on a shared server. One benefit would be that you will get better search engine positions as a dedicated IP generally means a faster loading website. What's more, you need such an IP when you intend to acquire an SSL certificate for your website and secure the information that your visitors submit on it.