Yev here from Backblaze -> the company started by providing unlimited online backup, and that's a great industry for us. About 4 years ago we released Backblaze B2 Cloud Storage, which allows developers or sysadmins or enthusiasts to directly upload/retrieve data to/from our data centers. Our core competency is data storage - so while most folks do use us for a backup (either of their Mac or PC on the consumer side or servers/NAS devices with B2 Cloud storage) - what we really do is store and retrieve data.
Sort of, but not really, we just wrote APIs that let people talk to our pods directly. You can read about our architecture here (https://www.backblaze.com/blog/vault-cloud-storage-architect...) and check out the APIs and how we built them here (backblaze.com/b2/docs/).
I have data that is important to me (family photos, etc.) on my hard drive. I have a backups of that data running on a Raspberry Pi with an attached drive. If my house gets broken into, or burns down, or hit by a tornado, basically something Really Bad, Backblaze has a copy of my data offsite.
It is tempting to use Backblaze as my only backup, but like they describe on their site, their primary value is as a backup of your backups. Normally you should never have to use them, and if you do, it will be slow. Now if you are in a hurry they offer a service to ship you your data on a thumb drive or hard drive, but that gives you an idea of their primary use.