Literal illusions are visual phenomena that create a misleading perception of reality. They often involve images that appear to depict one thing but, upon closer inspection, reveal another meaning or object. For example, a picture might look like a landscape but also contain hidden shapes or figures within it. These illusions play with our brain's interpretation of visual information, leading us to see what we expect rather than what is actually there. Artists like M.C. Escher are known for their use of literal illusions, creating intricate designs that challenge our understanding of space and perspective.