If you have a website then you have a Web host. And if you have a Web host then you have chosen either a shared or dedicated hosting package. This means that you either share a server with other customers of a hosting company or use a server by yourself.
What is an IP Address? Websites are stored on servers. Servers are essentially computers that been set up to respond to requests for data from end-users on the internet. Each server has an individual Internet Protocol (IP) address -- 4 numbers separated by dots such as 123.456.78.9. The server's IP address generally stays the same all the time.
What is a Shared IP Address? When the Web was still in its infancy, each domain name had a different IP address. With the 'Net population explosion of the mid to late nineties however, the finite number of IP addresses began to share IPs.
These days most websites are hosted on shared IP addresses. This means that one server with one IP address can host multiple domain names. Since servers are able to determine (based on the domain entered in a user's browser) which domain is being requested (even though a request may be sent based on an IP with hundreds of domains) many sites owners have opted to use shared hosting and in turn a shared IP address because of the lower costs that are associated with such a hosting and IP package.
What is a Dedicated IP Address? A dedicated IP address is just that an IP address (and in turn a server) set aside or reserved specifically for one domain. This means that if someone types in the numeric form of the IP address (which rarely if ever happens) the sole domain associated with a dedicated IP address will always appear in the browser.
Dedicated servers (and IP addresses) enable administrator's full access to the entire bandwidth of the server, and as much disk space as is needed or is available. Since dedicated IP addresses are no longer the norm and it usually costs more to get one, Web administrators considering a dedicated IP address usually do so only for large websites or ecommerce web sites with a need for enhanced security.
And Everyone Wants To Know.
Do Search Engines Ban Shared IP Users? For quite a long time, many industry experts suggested (only suggested) that by blocking IP addresses you could dramatically reduce the amount of search engine spam. This implied that since shared IP address users (read websites) were bundled together on the same IP address, innocent sites could be banned from search engines. This has been widely discredited of late because of the overwhelming numbers of site owners that are using Web hosting services in an IP sharing environment. As such, it would be unprofitable to search engines to penalize a site based solely on an IP.