A backup is a copy of a site which is kept on another web server and could be restored if a problem occurs with the live website - an unsuccessful script update, an unintended deletion of some file or of your whole database, and so on. Restoring the website the way it was will eradicate or reduce the damage the issue may have caused, that is by all means a certainly better alternative than having to rebuild your entire website from scratch. While you could download a copy of your content on your laptop or computer, keeping a backup is a feature that most hosting providers offer as part of their packages. It's important to check out how frequently they do that, though, because some service providers generate a backup only once every few days, which may be far from enough for a booking website or an e-commerce portal where the info is updated each day. It's adviseable to see how easily a backup could be restored, which can be vital if some issue appears on your Internet site.