You never know when there could be a glitch in your server, or a lightning strike, so it's a good idea to take regular backups of your site. There are a couple of approaches, which I outline in the following sections.
The most important part of your site, and also the part that you will never be able to re-create, is the content contained in the database. You should back up your database pretty regularly; although, exactly how often will depend on the number of times you change your content. Here is a rough estimation of how frequently you need to make a backup: