It would be really bad if you have spent many hours and thousands of dollars on your website and one fine day you lose all the content on it because it is destroyed by a hardware failure. This happens to many websites and the number of websites loosing content to hardware failure just keeps increasing. The most common solution for this problem is to make a backup of your website. This means you need to duplicate and store all the files on your website and any other database information in a safe place.
There are many ways to do a website backup. The older method of making a website backup is to manually downloading all your files and folders and saving them on your local computer. This can be done with many tools. The most popular one is the FTP application or the SSH application. Other tools would be the phpmyadmin, or direct access to the database with an SSH connection. This will give you a file of your database which you can restore when needed.
Nowadays, there are other methods as well for a website backup. The most popular of these is to use the backup service provided by your web hosting company. Most web hosting plans these days come with a control panel that gives very easy and in some cases one click backups. There may be a limit on the number of times one can perform a backup in a given time. But see to it that there is an option to download these backups and store them on the computer. Some hosting providers give automated backups that can be scheduled.
One thing that should always be remembered is that the backup of a website is always the responsibility of the owner of the website. Hosting providers only provide backup tools but they do not run the backups.