Web Hosting Bandwidth
Bandwidth in its simplest terms refers to the amount of data that flows across a network wire in a given time period. For most web hosting providers, that time period is measured in a month.When you are buying insufficient bandwidth, you might find yourself in two undesired situations: paying, usually high fees, for the extra bandwidth your web site needed or having your web site shut off. Overbuying bandwidth is not a good thing either as it will put you in the position to pay for something you don’t use.

It affects the speed of your site, the reliability and uptime of the site, and even the professionalism of the website.
There are thousands of web hosting companies around the world offering anywhere from megabytes to terabytes of bandwidth from hundreds of different providers. When choosing a web host for your site, it is extremely important to find one with the perfect amount of bandwidth and the best providers.For most personal or small business sites that are opening up a website for the first time, not a lot of bandwidth will be needed. Whereas for large business and corporation websites, or sites that focus on file mirroring, hundreds or even thousands of gigabytes of high quality bandwidth might be needed. The simple way to figure out how much bandwidth you will need to run your site is to calculate the size of each page your website, usually in kilobytes, and multiply it by how many users you expect to access that page each month.
What is bandwidth anyway?
Let’s just see what bandwidth is. Bandwidth is the term that is used to denote the amount of data that has been transferred from your web space to the computers of your visitors. To put it simple, bandwidth is the amount of data that flows across a network wire in a given period of time. In web hosting industry this time period usually is one month. This happens simply because web hosting providers are also charged monthly for their huge broadband Internet connection. This is the cost that ultimately is then passed on to the consumer in the form price for their individual web hosting plan.

Bandwidth being such a delicate matter for a successful web presence, could you at least estimate the bandwidth needs of your web site? The answer is yes, you can estimate it, but you can never be sure of your estimate being perfectly correct because of all the variables involved.
How much bandwidth will your website use?
With so much variation among web hosting companies, it can sometimes be difficult to know how much bandwidth your website will need. So, how much is a gigabyte of bandwidth anyway? Let's put it in perspective. If an average web page, images and all is 50 kilobytes in size, your website could be viewed 20,000 times! For the average hobby website, that is more than enough. Let's further put that 20,000 in perspective. If each visitor to your website viewed an average of 4 pages per month, it would still represent over 5,000 unique visitors to your website every month. Now if your website has lots of pictures on it though, then one gigabyte of bandwidth will allow for fewer visitors.
The truth behind unlimited bandwidth
There are several web hosting companies offering unlimited bandwidth. However, there is more to it than what reaches the eye. Based on their experience, such web hosting companies know it is unlikely that web sites hosted on their servers get high levels of data transfer. Hence, they go ahead and freely advertise unlimited bandwidth. I would recommend that you read the small print and confirm this with the web host. But like I said above, the bandwidth requirements of a new site would be negligible compared to the data transfer offered by web hosts. For example, at the time of writing Lunarpages web hosting company was offering 2500GB monthly transfer.