I have written often about the advantages of making backups online to file storage services in the cloud. However, I have never written about WHICH services are worthwhile so here is that article.
The following is a list of the more popular services and my opinion of the strengths and weaknesses of each. I am also including the amount of FREE file storage space each service makes available.
1. MEGA
Mega is perhaps the greatest offer of all that most people have never heard of. It’s also the one that offers the most storage for FREE: 20 gigabytes. In addition, You can even obtain even more FREE storage space by various achievements, such as installing the mobile and desktop apps or referring a friend, each of which nets you an added 5 gigabytes of space. However, this extra free storage space only lasts for a year. If you are using that space, you will need to pay for it beginning in the second year. The first 20 gigabytes remains free of charge, however.
Another advantage of Mega is that everything is encrypted inside your own computer BEFORE the data is stored on Mega. Not even the Mega employees will be able to read your information, not to mention hackers and spies who seek to find your personal information. Some of the other services listed in this article do the same thing but (1.) not all of them do and (2.) I couldn't find statements about encryption in all the services when writing this article.
2. Google Drive
No list of online cloud file storage services could ever omit mentioning Google Drive, the huge online service. It works well, is easy to install, and is used by millions of people around the world.
Google Drive offers 15 gigabytes of FREE storage space. You will need to make a free Google account and that includes a number of other services that you may or may not want, including a Gmail address and access to all of Google’s office-style products, like Google Docs, Sheets, and Slides.
3. Microsoft OneDrive
Here is a service from another huge powerhouse: Microsoft. Like Google Drive, Microsoft OneDrive is part of a larger suite of apps and you access it through a free Microsoft account. If you own a Windows computer or use any other Microsoft products, including Skype, you already have one.
Signing up gets you 5 gigabytes of FREE storage space as well as access to a number of apps in the Office 365 package. However, I prefer the free Google apps and Google also offers triple the FREE storage space. (However, you might prefer the Microsoft Apps if you already use Microsoft Office.)
4. pCloud
pCloud is another online file storage service that many people have never heard of. However, its list of services appears to be top-notch. When you register for pCloud, you receive 2 gigabytes of FREE file storage space. You then can unlock up to 10 gigabytes for free by following the Beginner's Tutorial or with Invite friends. However, once you start paying for the service, you can never run out of file storage space. The service continuously accepts additional files although the storage fees will increase as you start to save more and more data.
A major advantage of pCloud is that the company is registered in Switzerland, which has strong privacy laws. As a result, I would trust pCloud to keep my files private more than I would trust Google, Microsoft, any other North American-based service.
pCloud also works with Windows, Macintosh, Linux, Android, and Apple's iOS operating systems (most other cloud-based file storage services only work with Windows and Macintosh). Another feature of pCloud that will appeal to some is that you may (optionally) have all of your mobile photos and videos safely backed up to the cloud through the Automatic Upload feature on your mobile device(s).
pCloud also offers an (optional) Public Folder, a special folder in your pCloud's file structure, which allows you to create Direct links to files and folders. You can then provide access to other people to files stored in the Public folder. It works like a file server for static content, but without having to run a file server on your home computer.
5. Sync.com
While Sync.com offers a robust and secure service, there is little that is "the best" offer in the service with one possible exception: Sync.com does seem to be the best service for sharing files with others. That may or may not be important to you. Also, Sync.com only offers a measly 5 gigabytes of FREE file storage space.
6. IceDrive
IceDrive is a relatively new player in the cloud-based file storage services arena. It claims to be the most secure service available (although I was unable to verify that claim) and IceDrive also offers a 10 gigabytes of storage space for free. All you need to do is supply your email address to create an account and it’s all yours.
There are numerous other providers of cloud-based file storage services. However, I limited this article to the major players.
Honorable Mention: NextCloud
Technically speaking, Nextcloud is not an online cloud storage provider. Rather, it's a self-hosted file sync and content collaboration platform, which provides free software you can install on your own server, and administer cloud storage yourself. That server (or servers) could be located in your home, in your place of employment, or in the cloud.
The benefit of a self-hosted product is that you get to keep your data on your servers, offering complete control and faster performance. While this might seem intimidating for beginners, or futile for serverless users, the service offers preconfigured hardware that runs Nextcloud out of the box.
As free open-source software, you can download and install it at no cost, but need to factor in the cost of setting up, running, and administering your own servers. However, if you already have infrastructure in place, using Nextcloud instead of a commercial cloud storage solution could save you money.
I would recommend NextCloud only to experienced technical experts, not to computer novices.
You can learn more about NextCloud at: https://nextcloud.com.