A backup is the copying of important data in case the original data becomes damaged or missing for some reason. Having a recent backup at all times of the data stored in your web hosting account is absolutely critical as it provides you a safety net if something untoward happens. Even if you web host’s web server is 100% reliable and never has any problems (which is unlikely to be the case if you have a shared hosting account) there are still many ways in which data in your account could become corrupted or go missing:
You could accidentally erase or overwrite important files
Scripts you are using might be or become unstable and damage files
Your website could be compromised by external forces (spammers, scammers, hackers, and so on), causing data to disappear or be altered
You may also need to refer to old data that you’ve removed.
Even if your web host tells you that they automatically back up the data in your account daily, it is still of the utmost importance...