Challenge your mind with this optical illusion puzzle that tests your observation and problem-solving skills. The image ...

Challenge your spatial reasoning in this 40-second visual test that tasks you with counting every hidden triangle in a ...

THERE are different ways to put your brain to the test, from optical illusions that warp the way you see the world to tricky ...

Discover hidden triangles in an intricate puzzle that challenges your visual intelligence and pattern recognition in just 10 seconds.

The latest optical puzzle invites the public to solve a deceptively simple question: How many triangles are in this image? But don’t be fooled – this visual illusion is trickier than it looks.

Can you use an analogous approach to build a plane or a sphere or something more elaborate? Triangles — the simplest two-dimensional objects — serve as building blocks for more complicated ...