People are arguing over what animal they can see in confusing optical illusion

It's no secret brainteasers can be an incredibly fun way to past the time. Some optical illusions are perfect for testing your knowledge, while others ask what you see first which can determine your personality traits.

And if puzzles don't reveal your behaviour, they play tricks on the brain, and make you see things that aren't actually there. Optical illusions work when the brain and eyes try to speak to each other, but the interpretation gets mixed up. Now the latest image to really blow minds was shared on Reddit in the confusing perspective forum which boasts a whopping 2.1million members.

In the photo, which scooped 8,100 upvotes and hundreds of comments, the caption read: "Cat or pig?"

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Now, we know what you're thinking, it's obviously a pig – but that's where you might be mistaken.

If you look closely – and we mean really closely – you'll see it's actually a really large cat.

The colours, of course, resemble one belonging to a pig but you can spot the cat's eyes and tail when you focus or zoom in.

And then when you really think about it, why would a pig be roaming around like that, while a cat simply would?

Luckily we're not the only ones who were baffled as many Reddit users couldn't believe the answer.

One said: "Finally one that got me. I was absolutely certain it was a pig. Love it!" Another added: "Wait it isn't a pig?"

A third chimed in: "Aw man you're so right. I thought this wasn't confusing and obviously it was a pig, c'mon. And then I read your comment and took a closer look haha."

Then a fourth wrote: "I'm trying hard to see the cat here." While a fifth posted: "It's a very chubby cat. But yeah, the low resolution is not helping."

Optical illusions work by tricking the eye and brain into misinterpreting visual information, creating perceptions which don't match reality.

It usually occurs as our visual system takes shortcuts, makes assumptions about depth, motion and size based on patterns, light, colour and context.

Also it's the brain's attempt to make sense of a two-dimensional image as a three-dimensional world.