An IP address is a unique number which identifies a site or a server on the world-wide web, so if you have a dedicated IP, it will be employed exclusively by your Internet sites and shall not be shared with other individuals as it happens with shared web hosting accounts. Provided you have your own web server, you shall have a dedicated IP, but you may need extra ones for a variety of uses. In case you have an Internet store, for instance, you will need an SSL certificate for it, in order to make sure that the payment information your clients submit will be encrypted and safe. The same is valid if you have a login form of some type and you want the usernames and the passwords which visitors input to be protected. The SSL certificate requires a dedicated IP address, which ought to be different from the one which you already have on the web server. You may also need an individual IP for an app such as a VoIP server, or if you desire a slightly better performance for a given website, which may affect its position in search engine results.