Where do I need to back it up to?
I’m just going to guess that you don’t have a tape backup drive, you may not even have an optical drive. But, if you do, there is nothing wrong with keeping a backup, or more, on a disc. I don’t think I would do things that way, older technology slows the process down a lot.
Some broadband connection has enough upstream bandwidth to backup data through an online file-hosting service. Recovering data from a hard drive that died will cost a lot more than services that are “pay-to-play”.
Obviously, many people don’t have sufficient upstream bandwidth, or a data set small enough to make the online option viable as a complete solution. In that case, reduce your backup set (what you select to back up—don’t remove the data itself) to the bare minimum, keep it online, and then back up the rest locally using storage drives you attach to your computer or network.
If your data set is small you can just use a USB 3.0 flash drive, also known as a thumb drive. If you are backing up large data sets you would want to use an external USB 3.0/eSATA/Thunderbolt/FireWire drive. You can use both if you want, or alternate between the two is you don’t plan on using the online servers. You can still use them even if you do use the online server. You can use USB 2.0, but just remember that it’s slower and older.
There is also a network-attached storage (NAS) box that you can use. A NAS box lets you back up several computers on one network without having to drag a different locations. NAS boxes normally support rsync, that allows you to be able to mirror one remote location to another.
