The Stroop effect is a psychological phenomenon that demonstrates the interference between different cognitive processes. It occurs when individuals are asked to name the color of the ink used to print words, while the words themselves are color names that may not match the ink color. For example, the word "red" printed in blue ink can create confusion, leading to slower response times and more errors. This effect highlights the challenges of selective attention and cognitive control. It shows how automatic processes, like reading, can interfere with tasks that require focused attention, revealing insights into how our brains process information and manage conflicting stimuli.