Karnaugh maps are a method for simplifying Boolean algebra expressions. They allow visualizing the relationships between variables in a logic circuit to minimize logic expressions into their simplest disjunctive normal form (Sum of Products) or conjunctive normal form (Product of Sum). The document provides an example of a 4-variable Karnaugh map and simplifies the logic expression into its minimal form. In summary, Karnaugh maps are a graphical technique for simplifying logic expressions into their minimal sum-of-products or product-of-sums form.