We all love an online puzzle. But one that can teach you something about how different people's brains are maybe even better. From optical illusions to viral math problems, the internet loves getting collectively puzzled - then having a solution explained to them.

There is a whole range of brain-teasing puzzles online for you to try out. For example, have you ever seen Sudoku Escargot? It's known as the world's hardest ever Sudoku, and it's not for the faint of heart.

Of, if Sudoku isn't up your street, why not consider these infamous Logic Mazes? They'll make so super frustrated - but there's no satisfaction quite like solving one for yourself.

Logic puzzles not your thing? How about a riddle. What month of the year has twenty-eight days? Think about it - it's all of them. Or how about, what is full of holes but still holds water? Give up? It's a sponge!

Optical illusions are also super popular puzzles on the internet. Remember back in 2015 when we all became obsessed with "the dress?" To some of us, it looked white and gold, while to others, it was most plainly blue and black.

After many fights, it was concluded that there was actually no right answer. As the GIF displays, depending on the light quality and filter, the dress could actually be perceived as either. Who's head is hurting?

Well, that brings us to the latest puzzle to take the internet by storm. People have been sharing images of a whole bunch of identical letters online. Or have they?

Check out this confusing picture. A whole host of Bs, right? Well, actually ... take a look at the top right corner. Did you spot it? One row down and one row across hides a secret P. Weird, huh? Let's try another.

Now, look at the L version. Nothing to see here, right? Wrong! There's a sneaky I in there, too. This time it's not in a corner - it's down on the third row, on the fifth column from the end. Did you spot it?

Finally, we have what might just be the trickiest of the bunch.

A whole bunch of Gs. But, as you surely know by now, it's not quite as it seems. There's a C in the mix too - can you see it? This one is also in a corner - but this time it's the bottom right. More specifically, it's on the bottom row, two Gs from the end.

Amazingly, most people can't solve these simple-seeming puzzles in ten seconds or less. Did you get any of them in time? And which one did you struggle with the most?