It all started back in 2006, when the TSA introduced the 3-1-1 liquids rule in response to a foiled terrorist plot. The rule was designed to make it easier for security screeners to check carry on bags, and it's been in place ever since. But what's really interesting is how different countries have their own unique take on carry on rules - it's like a fun game of "spot the difference" when you're traveling abroad!
For example, in the EU, the rules are similar to the US, but with a few key differences. You can bring containers up to 100ml in size, as long as they fit in a clear, resealable bag. And in Australia, you can bring some liquids, like baby formula and medication, in larger quantities - but only if you declare them at security. It's all a bit confusing, but hey, at least it's not boring!
Airline Carry-on Luggage Size: Everything You Need to Know - The Points Guy
Now, you might be wondering what happens if you show up at the airport with a giant bottle of shampoo. Well, let's just say you might be in for a disappointing experience - the TSA will likely confiscate it, and you'll be left to wonder why you didn't just check it in the first place. But hey, at least you'll have a good story to tell, right?