A backup is a copy of a website that is kept on an independent hosting server and can be restored if something wrong happens with the live Internet site - a failed script update, an accidental deletion of some file or of your entire database, etc. Restoring the site the way it was will take away or reduce the damage the problem may have caused, that's by all means a certainly better option than having to reconstruct your entire website from scratch. Although you may download a copy of your content on your computer, keeping a backup is a functionality that almost all hosting providers include as part of their plans. It's important to take a look at how often they do that, though, because some providers generate a backup just once every few days, which might be far from enough for a booking Internet site or an e-commerce portal in which the data is updated every day. It's adviseable to see how easily a backup could be restored, which could be essential if some problem appears on your Internet site.