Wernicke's area is a region in the brain located in the left hemisphere, specifically in the posterior part of the superior temporal gyrus. It plays a crucial role in language comprehension, allowing individuals to understand spoken and written language. Damage to Wernicke's area can lead to Wernicke's aphasia, a condition where a person can produce fluent speech but struggles to understand language and may use nonsensical words. This highlights the importance of Wernicke's area in effective communication and language processing.