Not everyone can understand the purpose of an optical illusion. But some puzzles are definitely confusing, whether it's a brainteaser you need "detective" skills for, or just a little challenge to find the five hidden dogs . Now if you think you have what it takes, a Reddit post is baffling minds all over the world. In a post on a forum designed for optical illusions, you have a standard grid but you have to look closely to see what it's all about. Its caption read: "All of these lines are straight." So it might seem easy to understand but take a look at the picture where you'll find it's harder than you think. It shows a grey grid with green lines all over, some of which are straight and others appearing to be bent. So what do you see? This optical illusion seems confusing because when lines appear bent but are straight it could mean it's an example of the Cafe Wall Illusion or the Hering Illusion. This is caused by brain processes that interpret surrounding patterns or backgrounds. These illusions can occur because your brain is trying to make sense of the visual information by using past experiences and context, which leads to misinterpretations. What is the Cafe Wall Illusion? This might be alternating rows of dark and light blocks which make parallel straight lines that appear curved or bent. And how do you know it's a Hering Illusion? This is when straight, parallel lines can seem to bow outwards when seen against a background of radiating lines. Whatever optical illusion it might be, it's certainly left people scratching their heads on the Reddit post. And since it was shared, it racked up hundreds of upvotes as one said: "This is genuinely irritating. Well done." While another Reddit added: "I hate it here." A third social media user commented: "Liar." And a fourth person chimed in: "No they're not! I refuse to accept that."