When we read about webhost we hear often the terms bandwidth and data transfer, and may wonder what they mean exactly.Although is a big difference in duties between them, there are some important points that make them interact.
Bandwidth refers to how much data can be transferred at the same time and data transfer refers to the amount of data transferred in a given time.

What should you know about the bandwidth and data transfer for your site?
       Your site is directly affected by bandwidth because when this si smaller the site loads more slowly.You certainly do not want this and therefore it is your interest to have some solutions to this problem.

How do we know what we need?
       First you need to think about how many visitors your site will have.Is true that this is impossible 

to predict but we can choose an optimistic prediction.If you already have a site then you can focus on the number of visitors you had in the past, but even here there is little chance of some accurate estimate.
It is better to buy a webhost package with plenty of bandwidth and in this way we can be sure that we’ll not lose visitors just because the server did not allow a connection.

Reduce transfers:
      If you want your site not to require too much bandwidth you can even reduce transfers. You can do this by building websites better structured and optimize their graphics. For example you can use CSS, call JavaScript externally instead of embedding in every page, remove comments, white space and unwanted tags.You can even limit your meta tag because having to many keywords it is not search engine friendly.
There are many things that you can do for more bandwidth and in the end is up to you to decide which of these are better suited for your needs.