I have been using USB connected drives to backup the computer for a while now. I can’t remember when I started but it was around the time when my daughter was born (Jan 2006). Before the USB drive backup system, I was using DVD disks, several of them and waiting a long time for the backup to complete. These backups were with an application that would attempt to compress the data and write out in their proprietary format to the disks. One day I had a hard drive crash and found the disks but I had not backed-up the application. I found the program later but the whole restore process was not pleasant. In came USB drives and I could backup the files intact without using a backup program and the world was well again.
Four years later, I am backing up to an online web storage solution called BackBlaze and I love it for the most part. The service took a very long time to do the initial backup but I have slept well at night since then knowing I have a copy of all of my files safe and sound. The service does not save a history of the files backed up though, nor does it contain a list of old files I do not have on my primary or connected hard drive.
I still save an archive of old files and such to two USB drives. The first is a 320GB drive used for the photos and videos we have taken over the years and the second is a 1.5TB drive for everything else.
Everyone needs a backup solution make sure you find one that works for you.