Bandwidth is amount of data that can be transferred from your web site to the world*. Space is well..just that. The space available to store documents. Let’s assume that your home page, the first page served to your visitors, has a file size of 50 KB, 15 KB for the actual HTML page and 35 KB for images included on that page - backgrounds, buttons, logo, photos, etc.. Lets also assume that your site gets 10,000 visitors per month and the average visitor views 3 pages of your site, also 50 KB each.* Based on those numbers, your site would serve: 50 KB x 3 Pages x 10,000 Visitors = 1500000 KB or 1500 MB or 1.5 GB per month.*

When looking for hosting you should have in mind if you need more space or more capacity for data transfer. Images take up quite a lot of bandwidth and music much more! If you can have other solutions for space then look for a hosting package with quite some bandwidth and store only most important files. An example can be bigger images that consume bandwidth, the reason is that free image hosts have a limit of bandwidth and if you exceed it all images in that account will be replaced with a “bandwidth exceeded’ image. This isn’t professional-looking so avoid it.

Some image hosts are: Photobucket.com, Freeimagehosting.net, Imageshack.us
Some file hosts are: Files-upload.com, Filefactory.com, Box.net, Ripway.com

*Credited to showtheplanet.com