Unless you can afford to lose all the information and whatever else you have stored on yours, backups are a fact of life. I don't know of many computer owners who, over the period of time, have not suffered some electronic disaster or other that compromised the contents of their hard drive. If it hasn't happened to you, rest assured, it will. If it has, you don't need to be convinced about backing up your data. You can use a number of different devices with removable storage media for your backup.
Tape is the preferred choice among most experienced users.
Zip drives, Jaz drives, and more currently, CD-RW also play a role today. Regardless of your choice, you are going to need a good backup program to transfer the full or partial contents of your hard drive on to your selected storage media. If the name sounds oddly familiar, you' re right. It used to be Seagate Backup Exec, recently acquired by Veritas Software, an old name in the field of information storage management software. They didn't buy Seagate, only their Backup Exec.