ELI5 the cloud. How does it work ? Can I just download all the things I want to so it doesn't take up space on my SSD by uploading there or something?
"The cloud" basically just means "someone else's computer(s)". It takes away a lot of the black magic once you translates the buzzword.
It's marketing speak for someone else's computer.
To tack on to this, with an example that is easier to grasp - I have my own cloud, comprised of machines at my house, my friends, and family.
Those machines provide backup storage for each other, over the internet (using an encrypted connection).
If I were to charge people for storage, I'd be little different than any other cloud storage provider (at the most basic level).
IMO the main pro of cloud storage is that the provider's engineers are much better at doing backups than you are. You won't lose your data if, like most people, you only have one copy of everything and your hard drive is destroyed.
The main con is that the provider can deny you access without warning. You probably won't get an explanation or a real chance to appeal the decision.
So far that second thing hasn't been a common problem for normal users but I would still keep local copies of the data which I can't easily replace.
As a cloud systems engineer who has experienced data failures in multiple consumer cloud services, I do not trust cloud services as a backup just because they are cloud services.
Your second point is why paying for such services makes a real difference.
Companies like storj.io, backblaze, or any other cloud storage/backup provider provide a service for a fee with (not really) clear usage rules. If you're encrypting your stuff before it goes to the cloud, you're pretty safe from scanning, and if you have a contract for a given space and bandwidth, the worst you'll probably run into is overage fees.
If all you are looking to do is free up ssd space, just add another ssd or hdd. It will save you money by not having to pay a cloud subscription fee depending on how much you are trying to store. A decent ssd for speed and storage will cost you prolly $150-$250. For a cloud service you'll prolly be looking at $50/year per 1tb of storage. The catch is tho, you stop paying... you loose everything you had on the cloud that wasn't backed up to a physical device. You're guna want your shit backed up as a safety measure anyways because you can't control much of anything if all your pc data is on some company's cloud server. They increase prices, tough shit. They have security breaches, tough shit.
I'm sure a bunch of lemmy users can chime in with self hosting cloud options for secure cloud storage or something along the lines but I'm answering with an understanding that you might not be ready to dive that deep into something like that.
Cloud storage is good if you are in school, travel alot, work on office on somedays while working from home others, or for sharing data between multiple parties.
If everything you do is going to be on your own local pc, then fuck the cloud.
Oh yeah one last thing, if you delete a file on the cloud, there is no recovery wizard, that ahits gone doggy. I can thank Dropbox for that harsh lesson.
By "the cloud" people are generally referring to all the services and storage that you are connected to across the internet. This exists on other computers owned by companies or other individuals. Yes there are lots of storage services available from Apple iCloud to Google Drive to OneDrive (Microsoft) to lots and lots of others. They tend to work in slightly different ways. Some just "backup" your device and you can't really use them as a replacement for browsing photos for example. Others do exactly this. Most have a small amount of free space available after which you pay. If you are looking to free up space on your SSD I would make sure the one you go with is a well known, reliable one, as they will be the only ones with a copy of your data- you want to make sure they look after it properly!
For many things you need a computer, that runs all the time, that is connected to the internet, that has not too much and not too little performance. You want to run a website, a forum, a file server, a ...? You need just such a computer. Cloud is a large word, that essentially refers to services, where you can easily rent a computer of your choosing for money, to run any and all services on. What you are refering to is probably cloud storage, where the service is, you can send and receive files from a server. The technical details can become complicated, how to ensure the files are always up to date, what if you make different changes on different devices at the same time, do we create a local copy or do we stream all file interactions. But the summary is this: There is a computer somewhere else, running a service, being rented from a cloud provider.