Welcome to 2018, where the news just keeps getting better and better. Just kidding — researchers have just discovered two massive security flaws in computer processors, and they affect most of the computers in the world.

That includes mobile phones, tablets, laptops, desktop computers — you name it, there’s a good chance it’s affected. It doesn’t matter if you’re running macOS, Windows or Linux, either, so don’t get smug. Oh, and the fixes in the works are likely to slow down your computer. In short, this is a huge deal, and it’s going to affect you, but there’s also a lot of random useless panic floating around. Here’s what you need to know:

Explain The Problems To Me Like I Know Nothing About Tech, Please

There are two different security flaws involved here, and as with most big tech vulnerabilities, they have predictably dramatic names: Meltdown and Spectre.

Both are tricky to explain, but essentially they’re problems to do with processors (a physical chip inside your device), which in theory allow an attacker to access passwords and other sensitive information stored deep in what is supposed to be an inaccessible part of the computer.

Basically, there’s a part of your computer’s memory called the kernel, which is the central part of the operating system. It handles the serious stuff, often including passwords, and it’s supposed to be separate from the part of your computer that runs the programs you use. Meltdown and Spectre mess with that separation in different ways, allowing everyday programs to pretty much look into the kernel and grab passwords and other sensitive data.

Luckily, I still have one machine I can use to write stories that is not affected by the Meltdown or Spectre attacks. pic.twitter.com/AaRdxsgVV1

— Stephen Nellis (@StephenNellis) January 4, 2018

This is a problem for our personal computers, but it’s a huge problem for things that run in the cloud. The data you store in the cloud and the programs you use online are stored on servers, which are basically giant computers. Lots of different programs and services might run on one server, from a tiny personal website to a big one like Facebook.

The flaws announced today mean a hacker could, in theory, buy a tiny bit of space on a server, and then use that to have a look at the passwords being stored by someone else on the same server (say, Facebook). And that’s pretty scary.

Oh Shit, Can We Fix It?

There’s more to it than that, but that’s the basic gist. The important thing to note is that Meltdown and Spectre are different, and that means there are different fixes. Operating systems like macOS, Windows and Linux are releasing updates to protect you from Meltdown — you’ll get one of those things asking you to install an update soon, and you should do it ASAP.

Spectre, on the other hand, has no fix at the moment. It’s going to require us to redesign the way we make the physical chips that go inside our computers, which means that true to its name, it’s going to haunt us for a while.

Also, you might have seen headlines today claiming that this is somehow just a problem with Intel processors. That’s not actually true — while Meltdown has only been found to affect Intel processors (so far), Spectre affects everyone.

What’s This About Slowing Down My Computer??

The other headline you’ve probably seen a lot of today is something scary about your computer slowing down as a result of the fixes (cue gamer tantrums).

This is partly true, but it’s not time to panic just yet — the fixes are projected to slow down some things on your computer by anywhere between 5 and 30%, but it’s too early to know whether this will be a big deal for the average user.

What Now?

In short, install your updates when you get them, and then be patient. While researchers and manufacturers have known about these flaws for around six months and have been trying hard to fix them, there’s still a lot we don’t know (e.g. how much computers will be slowed down, whether hackers have actually exploited these vulnerabilities before, what we’ll need to do to fix Spectre).

If you’d like to know more about how the flaws work in detail, start with this Twitter thread by New York Times cybersecurity reporter Nicole Perlroth. Then try this site, created by the people who discovered the flaws, which includes a great, relatively simple overview of both Meltdown and Spectre, the difference between the two, and a big FAQ. This post is also a good (dense, but readable by someone who doesn’t know a lick of code) explainer.