A backup is a copy of a website that is kept on a separate web server and could be restored if something goes wrong with the live website - a defeated script update, an accidental deletion of a file or of the entire database, etc. Restoring the website the way it was shall remove or limit the damage the issue may have caused, that is by all means a much better alternative than having to reconstruct your entire website from scratch. Though you can download a copy of your content on your laptop or computer, keeping a backup is a function that nearly all hosting providers offer as part of their plans. You must take a look at how often they do that, though, because some companies generate a backup once every couple of days, which might be far from enough for a booking Internet site or an e-commerce portal where the information is updated daily. Make sure that you see how quick and simple a backup could be restored, which can be critical if some issue appears on your Internet site.