In web hosting terms, traffic is singularly defined as bandwidth. Bandwidth, by definition is the amount of data that flows between your web server and its users. It is measured as the total amount of data coming in or going out of your website. Therefore, considering the bandwidth offered is a crucial concern.
Every time someone accesses any page on your site, the visitor effectively downloads all the images and files that are contained on the page, thus consuming bandwidth. An image, for example, is a larger file than a text file so visitors accessing an “image heavy” site will consume the bandwidth quickly. If your website is text based, the bandwidth consumed is less. A complicating factor is that an attractive site carrying a lot of graphics may attract a greater number of hits than a text based site. Therefore, you must not only take into account the number of visitors to your site, but also the actual content on your website when considering bandwidth. This could approximately be calculated as the number of hits your website receives multiplied by the size of the pages on your website.
We hosting companies generally limit the bandwidth on a monthly basis and charge separately for the amount of bandwidth consumed in addition to the set amount. Although there are some plans that have unlimited bandwidth options, they are expensive.
For small and medium sized websites, the bandwidth offered by the most popular plans would be more than enough. A website needs excellent promotion for the first six months or so, depending on the domain, before bandwidth crops up as a contentious issue.
In considering bandwidth, you need to be realistic about the amount of traffic you expect to receive and the potential for growth. In choosing a web hosting provider, you should consider ones that offer a number of plans with different bandwidth sizes so there is the ability to upgrade easily without moving to a completely new web hosting company.