Series of classic optical illusions demonstrating how perception can be tricked by visual patterns and perspective.

- a: Optical illusion forming a bird and a bush
- b: Abstract pattern resembling a brain or neural network
- c: Six circles arranged in a hexagonal pattern
- d: Two elephants, one larger and one smaller
- e: Profile of a face with glasses
- f: Four stylized figures standing side by side
- g: Bearded man’s face surrounded by foliage
- h: Radial pattern with concentric circles and a central dot
- i: Grid of black squares on a white background
- j: Chalice or goblet shape
- k: Geometric pattern with interlocking lines creating a maze-like effect
- l: Starburst pattern with rays emanating from a central point
- m: Silhouette of a person holding an object
- n: Two converging lines forming a triangle
- o: Three crescent shapes arranged in a circular pattern
- p: Profile of a person with flowing hair
- q: Wireframe cube with visible edges
- r: Wireframe cube with a small circle inside