Carbonite is online backup only, so it doesn't really work well for local backups or backups to external drives. You'll still have to handle that yourself. You can try Carbonite for free for 15 days, but after that you'll need to pay up $60/yr to back up one computer with their Home plan, $100/yr to back up one computer with their Home Plus plan, and $150/ur to back up one computer with their Home Premium plan. You can read more about Carbonite's plans and pricing here.
Michael Muchmore is PC Magazine's lead analyst for software and web applications. A native New Yorker, he has at various times headed up PC Magazine's coverage of Web development, enterprise software, and display technologies. Michael cowrote one of the first overviews of web services for a general audience. Before that he worked on PC Magazine's Solutions section, which covered programming techniques as well as tips on using popular office software. He previously covered services and software for ExtremeTech.com.
By not restricting you to the sync-folder model of cloud storage, you don’t have to worry about making sure you’ve actually moved all of the content you want to backup into that single folder. This also means that if you need to replace your computer because of a hard-drive crash or other mishap, you can restore your exact file structure on your new device.
The number one reason to download the entire YouTube channel is that you’re going to have offline access to them. If you want to catch up on your favorite shows but you’re going to be without internet for a while you may want to have a way to do it without the internet. Being able to get access wherever you happen to be, directly on your device, is going to be an important step. It’s going to make sure that you have something to do during that time that you’re away from internet access or not wanting to use your internet access (which is another great reason).
One of the biggest advantages of using an online backup service is that it lets you access your files from anywhere. Most online backup providers let you view and download files from a web browser, but that should be the bare minimum. Many also include file-sharing options, the best of which even let you specify a password for access and an expiration date for the shared item.
SpiderOak is well known as one of the most privacy-centric cloud storage services, but it's also a great backup service. The same power and features that you get for file syncing and access extend to its backup client, and SpiderOak's "Zero Knowledge" policy extends to your backups as well. Even they don't know what you're storing on their servers, and all of your data is encrypted on their servers and before it leaves your computer. The SpiderOak desktop client has a fully-featured backup tool in it that lets you back up your entire desktop, documents, email, music, or movies right to the cloud, or you can hit the "Advanced" tab and pick the files and folders you want to save, including external drives, network drives, or anything else on your computer. As you add files to your backup job, you'll get a live preview of how much space you'll use with what kinds of files, and whether you have space for it. SpiderOak supports Windows, OS X, and Linux, has mobile apps for iOS and Android, can do incrementals, and if you uncheck a file to stop backing it up, the files will still live in your SpiderOak account, just as an archive. Your backups happen in the background, or when you schedule them.
Jihosoft 4K Video Downloader is available as a completely free system that actually works for both PC and Mac users, but there’s a paid version as well. What’s really great about this YouTube video downloader is that it actually works for just about any kind of video you want to download, whether that video comes from Facebook, Instagram, Twitter, SoundCloud, or YouTube, so you’re not stuck with just one platform. You’re also going to have the option to download in just about any resolution and still get all the audio and subtitles that usually come with the video. On top of all that, you can convert to any video format or even MP3 audio, so you’re always able to watch (or listen).
BackBlaze doesn't have an offline component, so you'll have to handle that yourself, but it's by far one of the most affordable options on the market. Accounts are $5/mo (you get a break if you pay up front for one or two years), and you can add more computers to the same account for another $5/mo. You can read more about Backblaze's pricing options here.
Since you're probably going to be paying for a backup service for years, cost is an important factor to consider. All the services rounded up here are subscription-based, but they partition their features and fees differently, so it's worth comparing plans closely before committing to one. Most construct pricing tiers based on the amount of cloud storage included, however, or by the number of devices you can use with an account. A few services offer permanent free accounts, but those plans impose paltry storage limits or restrict key features to the paid versions. Watch out for file-size upload limits as well.