Bandwidth is a web hosting term used to describe how much resources a website consumes on a web server. In more familiar terms, it is the rate and volume at which visitors request information from your website. 

Every website consumes bandwidth because whenever someone clicks on a link in your page, the web server is tasked to load that page into the visitor's browser. 

Sites with large traffic will consume more bandwidth than ones with low traffic. Again, sites with large files will consume more bandwidth than those with smaller files because the server then needs greater "energy" to send the large files. 

Web hosts charge for their services according to bandwidth. From the equity point of view and to ensure fair charge, they price hosting packages on the basis of how much load your site exerts on their servers. 

How much bandwidth you need for a site will depend on the type of site you run. A site which sells baby dolls and has a traffic density of 100 visitors per day will need about 3 GIG of bandwidth for a month. 

A site which offers an online magazine will need about half that amount because a magazine is only read. There is no interactivity which will let the server process anything. 

However, if you run a site with 1000 products in a catalogue or an ecommerce website with a shopping cart, with 1 million visitors a month, then you will need 10 GIG of bandwidth.

Compared to the doll site, this figure looks too big but there is a reason. When too many people try to access a site at the same time, there is congestion so the extra bandwidth opens up the server the more to facilitate speedy access of files. 

This is how to calculate bandwidth:: Multiply the size of your website by the number of visitors in a month. So if you have a website which is 1 MB in file size and has 1 million visitors in a month, then your bandwidth need is 1 GIG.

You can know the size of your website by right clicking on your site folder and clicking properties. The number of visitors can be estimated or seen from the web statistics tool provided by your host. 

If you have a big site with large traffic, bandwidth can consume a lot of money. You can reduce your costs by reducing the size of your images with a file compression tool. 

Every website needs optimum bandwidth to function. You cannot do without it but you can adopt a variety of ways to reduce the costs that come with it.