There are two methods that I will go over, using local storage or cloud storage. Some people will use both methods since you can never be too safe, as long as you pick one or the other, you can rest assured that you have a backup of your files.
If you have just a few albums to backup then I would recommend buying yourself a simple 8GB or 32GB USB thumb drive, you can estimate the cost to be $0.50 per GB. This is great for those that are constantly on the go and need their data fast. You can also get a portable hard drive which are capable of storing up to 4TB of data. That’s over a million songs or over 4 million pictures!
There are many free options available that offer up to 18GB (with referrals). Finding a solution that offers 5GB of storage is common, here are a few providers that I would recommend: Drobbox, Google Drive, Microsoft SkyDrive, and Box. There are also other Cloud storage providers that offer automated remote backup of your data. Mozy, Backblaze, LiveDrive and SOS Online Backup all provide this feature.