What is Bandwidth?
Bandwidth refers to the amount data that is downloaded from a web page.
For example - if someone lands on your home page - they download the text, colors, styles and images of that page and all files making the page work behind the scenes. Even fonts that we use on the site that are hosted at google - have to be pulled down. They "use up" bandwidth.
You however only see the bandwidth usage for the items hosted on your site. So when we host a video at YouTube - we don't use your bandwidth -only YouTube's bandwidth. Same with Google fonts - hosted on Google - Google's bandwidth. Thank you Google!
When you get a lot of traffic - the bandwidth is high because hundreds or even thousands of people are visiting your pages and actually downloading all of that data without even knowing it.
The good news is this means your site is getting hit with visitors - or in some cases "bots". Bots we can control to slow down bandwidth by identifying them and blocking them.
Since bandwidth is pretty cheap - it's easy to upgrade. But most hosts like us have to limit it just to make sure we are fair with our customers who share servers.