As VPN editor at Tom's Guide, I write about the best VPNs day-in, day-out. I like to think that I've got a good understanding of the underlying concepts that make VPNs tick, and the jargon that often surrounds privacy software.
Of course, as a writer, it's my job to explain these simply and help you understand how VPNs work, no matter your level of expertise. Sometimes, though, I can fall into the trap of assuming too much shared knowledge from my readers.
To get a fresh view of how to explain VPNs in a very simple way, I thought I'd put ChatGPT to the test and get it to explain gradually more complex VPN features "like I'm five". The results were remarkably effective – although certainly not perfect.
What is a VPN?
We'll start off with something simple – what is a VPN?
ChatGPT says:
"A VPN is like a magic tunnel for your internet. Imagine you’re walking to your friend’s house with a big map that shows exactly where you’re going. Normally, people can see where you’re walking and where you’re headed. But if you use the magic tunnel (VPN), no one can see you or where you’re going. The tunnel keeps your journey secret and safe, so only you and your friend know what’s happening. That’s what a VPN does—it hides what you’re doing online and keeps it private."
I quite like ChatGPT's comparison here, and while explaining things as "magic" is often a bit of a cop-out when it comes to tech, we are explaining something to a five-year-old.
I'd argue that this perhaps misses out on one of the most important things that a VPN does, which is rerouting you through one of its servers. This step effectively means that your "friend" – the website you're heading to – actually can't see exactly where you've come from, and instead thinks you've come from somewhere completely different.
On the whole, though, the magic tunnel analogy works pretty well, and explains the concept of a VPN at its most basic level in simple terms.
What is encryption?
ChatGPT says:
"Encryption is like using a secret code to keep your messages safe. Imagine you have a note you want to send to a friend, but you don’t want anyone else to read it. So, you change all the letters into a secret code that only you and your friend know how to read. Even if someone else finds the note, they won’t understand it because they don’t know the secret code. That’s what encryption does: it scrambles information so only the right people can understand it."
Again, this isn't a bad effort – encryption does "scramble information so only the right people can understand it."
I do feel that the concept of an encryption key could be worked in here. If you're not sure what that is, the way someone can unscramble encrypted data is through the use of a "key," which you share secretly with whoever you're sending stuff to.
Given another shot, I'm sure our AI pal could've worked in the concept of a key – but you only get one go at this test.
What is split tunneling?
ChatGPT says:
"VPN split tunneling is like choosing which toys to share and which ones to keep to yourself. Imagine you have a box of toys, and you decide some toys can go out and play with everyone, while others stay hidden just for you. Split tunneling is when your computer picks which stuff goes through the safe VPN tunnel and which stuff just uses the regular internet. It’s a way to keep some things super safe while letting other things go out the normal way."
I think ChatGPT took the "five" of "explain like I'm five" a bit too literally here, and the first section goes a little off-piste. We could lose all the stuff about toys and answer the question with the final couple of sentences – which, admittedly, make a great explanation of split tunneling.
What is a VPN protocol?
We're getting a little more technical now, but ChatGPT absolutely smashed this one. It says:
"A VPN protocol is like the set of rules a secret tunnel follows to keep your internet connection safe and private. Imagine you're sending a message to a friend, but you want to keep it hidden. The VPN protocol decides how the message travels, like choosing which path to take and how to lock the message with a special code, so only your friend can read it. Different protocols have different ways of doing this, some are super fast, while others are extra secure, but they all aim to protect your message on its journey."
I'm not sure our robot friend has left much out here, especially at this level of simplicity. It's even mentioned that there are protocols better suited to some purposes than others. I'd be lying if I said I wasn't just a little impressed.
What's the difference between OpenVPN and WireGuard?
ChatGPT says:
"OpenVPN is like an older, well-tested tunnel. It’s been around for a long time, and everyone knows it works well. But it’s a bit complicated and can be slower because it takes a lot of extra steps to keep you safe.
"WireGuard is like a newer, faster tunnel. It’s simpler and quicker, so you can zoom through it easily. Even though it’s newer, people like it because it’s both fast and secure.
"So, OpenVPN is the old reliable tunnel, and WireGuard is the new speedy one!"
I'm a big fan of explaining technical concepts in physical ways, and while I'm not really sure whether ChatGPT is trying to explain a VPN tunnel in physical terms, I can't help but think of an old coal mine.
OpenVPN is the "old faithful" tunnel that's never collapsed, while WireGuard is the newest tunnel built with all the latest mining tech. I like that explanation.
One thing I would argue is that OpenVPN isn't necessarily slower because it's taking extra steps to keep you safe. Rather, it's more like a tunnel that's been redirected a few times, and takes a more meandering path, whereas WireGuard is straight as a die and gets you to your destination as quickly as possible.
That's all before you consider the fact that OpenVPN was created at the turn of the millennium, and was never intended to hit the kind of internet speeds we see today.
What's the difference between OpenVPN UDP and TCP?
Now we're getting into the complex questions that take a little more simplifying to make digestible, but ChatGPT again makes it very easy to understand. It says:
"Imagine you're sending a letter to your friend. With OpenVPN UDP, it's like sending your letter really fast without worrying too much if every little detail arrives perfectly. It's super quick, but sometimes a tiny piece might get lost, and that’s okay because it’s still fast and usually works just fine for things like watching videos or playing games.
With OpenVPN TCP, it’s like double-checking every single part of your letter before it gets sent. It makes sure nothing is missing, even if it takes a little longer. This is better for things like sending important information where you can’t afford to miss anything.
So, UDP is like fast mail, and TCP is like careful mail."
The only question I have is... do kids still send letters these days?
What is post-quantum encryption?
ChatGPT says:
"Post-quantum encryption is like building a super-strong treasure chest that even future super-smart robots can’t break into. Right now, our locks are strong enough to keep regular thieves out. But someday, there could be super-powerful robots (like quantum computers) that are really good at breaking locks. Post-quantum encryption is making sure our treasure chests stay safe, even when those super-robots show up. It's like planning ahead to keep your secrets safe, no matter how clever the bad guys get in the future!"
I think this might be my favorite simplification of them all. Future robots? Check. Treasure chests? Check. Keeping my secrets safe no matter how clever the bad guys get? Check.
While we're missing a lot of nuance about how post-quantum encryption differs from regular encryption, and why it's important to consider post-quantum protections even today (hello, store now, decrypt later attacks), this is an excellent six-line explanation that I challenge anyone not to understand.
What's the difference between NordVPN and ExpressVPN?
My final question was a little different, and I decided to see what ChatGPT had to say about two of the most popular VPN providers. It says:
"NordVPN and ExpressVPN are like two different kinds of superhero shields that keep you safe when you're on the internet.
NordVPN is like a big, strong shield with lots of extra tools. It has tons of options, like blocking bad guys and even hiding you better in crowded places. It's really good for people who want lots of features and don’t mind having more buttons to press.
ExpressVPN is like a super quick and easy-to-use shield. It’s super fast and simple to set up, so you can start using it right away. It’s great for people who want something that just works really well without fussing with too many settings.
So, NordVPN has more tools, and ExpressVPN is quicker and simpler to use!"
By and large, this tallies with my opinion on both providers, possibly because a lot of my content has been used to train the LLM. If we disregard the goofy "big, strong shield" wording, it's a great comparison between the two – in our NordVPN review, we found that it is very comprehensive and has tons of buttons to press, while in our ExpressVPN review, we found that it is incredibly simple and easy to get up and running.
One nitpick is the fact that in our testing, ExpressVPN isn't one of the fastest VPNs, although it could be argued that the final sentence means it's quicker to get set up.
Either way, ChatGPT has proven itself to be a, frankly, scarily good explainer of difficult VPN concepts – and while there's some nuance missing, it's certainly not far off in most cases. If this keeps up, I might be out of a job...
