An IP address is a unique number that identifies a website or a hosting server on the world-wide web, so in the event that you have a dedicated IP, it will be employed exclusively by your sites and shall not be shared with other individuals as it happens with shared Internet hosting accounts. In case you have your own server, you shall have a dedicated IP, but you may need extra ones for different purposes. Provided you have an online store, for example, you shall need an SSL certificate for it, so as to ensure that the payment information that your clients submit shall be encrypted and secure. The same is valid in the event that you have a login form of some kind and you wish the usernames and the passwords which visitors type in to be secured. The SSL certificate requires a dedicated IP address, which has to be different from the one that you already have on the hosting server. You could also need an independent IP for an app such as a VoIP server, or if you would like a slightly better functionality for a given Internet site, which may affect its position in search engine results.