An IP address is a unique number that distinguishes a website or a web server on the Internet, so if you have a dedicated IP, it'll be employed solely by your Internet sites and won't be shared with other individuals as it happens with shared hosting accounts. Provided you have your own hosting server, you'll have a dedicated IP, but you may need extra ones for various uses. Provided you have an Internet store, for example, you'll need an SSL certificate for it, to make certain that the payment info which your clients submit shall be encrypted and secure. The same is valid if you have a login form of some type and you want the usernames and the passwords which visitors type in to be secured. The SSL certificate requires a dedicated IP address, which needs to be different from the one that you already have on the hosting server. You might also need an independent IP for an application such as a VoIP server, or if you want a slightly better performance for a particular Internet site, which will influence its position in search engine results.