In the Web hosting industry there are two types of IP address...
Dedicated IP address (also called static IP) means that a website has its own IP address. Whether you type in your URL or the numeric form of its IP address, both will bring you to the same domain.
Shared IP address means that multiple websites share the same address. Web servers can determine by the domain entered in a user's browser which website is being requested. Typing in the IP address will bring you to some kind of generic page instead of the specific site you want.
Due to the rapid increase of the number of registered domain names and the finite number of IP addresses, Web hosting providers are forced to use shared IP's when possible. In fact, hundreds of websites often share the same address. Static IP hosting is no longer the norm and usually costs more.
In other words
a dedicated IP address is better than having a shared IP for your website...
Some SEOs suppose that there really is no good reason to obtain static IP Web hosting. Your site will not perform any better by having its own static IP.
Some others theorize that your choice of dedicated IP hosting vs. shared hosting might slightly affect your rankings (i.e. it's a factor considered by search engines).
Yet others suppose that sharing an IP address with known spam or adult sites raises a warning flag with search engines, so some of them may respond by banning the entire IP address from their index.
