You might already be familiar with the term ‘bandwidth’ from your broadband provider. At its most simple level, bandwidth is a term that refers to how much data can pass along an internet connection.
Traffic or Bandwidth means how much data is used on a website. If you have lots of visitors, you are getting a lot of traffic. When a user accesses your website, they send a request to the server and the server responds by literally serving up your website.
Think of it as like turning on a tap. The more that people visit your website, the more water is flowing along the pipe, until you reach a point at which the pipe is full of water and it’s running at full capacity.
The same idea applies to your website. If too many people are trying to access it at the same time, the pipe is filled up and the site starts to slow down and even to stop working altogether. And your hosting bandwidth is what determines the width of that pipe.