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