Below we are going to look at some of the reasons you may want to choose disk based over outside server based backup options.
When you backup to an external disk from your computer, you are creating a physical representation of your entire hard drive. This makes it easy to utilize your replica to restore your original system quite quickly. If your hard drive gets stored on someone elses server, you're not making yourself quite as secure. What is stopping their servers from crashing and losing your information the moment you need it?
Another advantage to disk based backup software is that you can create as many copies as you want. If you want to copy it just once that's okay. If you want to create multiple copies to keep in different locations for better security, that is even better depending on the nature of your business. It is recommended that you keep the backup copy in a different building from the computer in case of natural disaster or fire.
There are a variety of disk types you can use to backup your system on. There are CDs, external hard drives, flash drives, and many other types of media that can be utilized for your hard drive backup.
Backup software that uses hard disks as a method of creating that alternate copy of your information have numerous advantages over external server based methods, as you can see. I highly recommend using the hard disk method, as it gives you an extra layer of protection.