You need to know the difference between shared and dedicated IP addresses when finding a web host. Some websites don’t need a dedicated IP address and can function just fine on a shared IP. However, for the serious webmaster a dedicated IP is preferred over shared IP addresses.
Shared IP addresses have a few problems that can spill over onto your site even if you are squeaky clean. Now, first you must understand what an IP is! Every domain name that is home to a website has an IP address assigned to it. This address is the real address of a website or server. Domain names were developed because the long IP numbers like 243.132.77.6 were clumsy and hard to remember. Shared hosting (where there are hundreds of websites sharing one server) will entail all sites in that server sharing one single IP address. Kind of like your site is living in a commune. One big happy family.
For the hosting company, this is desirable as it simplifies the technical aspects of hosting all the different websites. Since no-one has a unique IP address for their domain, they can all share one IP address. This makes it easier for the host to manage and maintain the servers.
The downside to shared IP’s is that if someone else gets in trouble for spamming or scamming, the entire IP can get banned or blacklisted. Suddenly your site disappears from the search engines or your email starts getting blocked by ISPs. In shared hosting the actions of others on the same server can affect your site adversely. Kind of like the commune getting classified as a cult with a bunch of armed militia types. No-one really trusts you.
Most larger websites or ecommerce enabled sites have dedicated IP addresses. In this case, your site will be the only one on the internet with that unique IP number. If you have a business oriented website then you need a dedicated IP address for your site; especially if you accept any types of credit card payments on your site. This is because you won’t be able to get an SSL certificate for your website unless you have a dedicated IP address. You can get around this by using a PayPal shopping cart or something else hosted off your site, but this doesn’t engender trust in your customers, when they find out your site isn’t a SSL certificate holder and you have to send them offsite to complete a transaction.
Some SEOs also feel that sites with a dedicated IP address do better in the search engine results than those with shared IPs. If you have a shared IP, don’t panic – for a charge your hosting company will usually be able to upgrade you to a unique IP.